Started the truck and the ignition switch/key is stuck in the run position. It has tilt steering column. I started the truck, moved it a short distance, put it in park and went to turn the key off, the ignition switch would not move.

Hi there,

Removal

Disconnect the negative battery cable with the proper size wrench and place away from the battery.
Insert the key into the ignition lock cylinder and turn the key to the run position.
Remove the steering column cover on a tilt steering wheel model by pressing the upper and lower section of the cover together and pulling free from the mounting plate. Remove the steering column covers on a non tilt steering wheel model by using a Philips screwdriver and unscrewing the mounting screws.
Disconnect the electrical connector from the ignition switch by lifting up on the release tab and pulling.
Press the ignition switch actuator pin by pushing a small screw driver into the key lock cylinder, while doing this pull the ignition switch out of the ignition switch housing.

Installation

Insert the new key into the new ignition switch and turn the key to the run position. Insert the new ignition switch into the ignition switch housing. Wiggle the switch back and forth until the actuator pin mounting hole is aligned and falls into place.
Install the electrical connector back into the connector housing by pressing it in with your hands.
Place the steering column covers back onto the non tilt steering wheel and insert mounting screws. Tighten screws using a Philips screwdriver. Place the steering column covers over the tilt steering wheel and press the upper and lower portion together to snap covers back into the mounting plate.
Pull on the ignition key to ensure switch is locked into place. Turn key to the "off" position and remove the key. Insert the key and start the vehicle.

Hope these help.

Disconnect the negative battery cable with the proper size wrench and place away from the battery.

Insert the key into the ignition lock cylinder and turn the key to the run position.

2 Remove the steering column cover on a tilt steering wheel model by pressing the upper and lower section of the cover together and pulling free from the mounting plate. Remove the steering column covers on a non tilt steering wheel model by using a Philips screwdriver and unscrewing the mounting screws.

3 Disconnect the electrical connector from the ignition switch by lifting up on the release tab and pulling.

Press the ignition switch actuator pin by pushing a small screw driver into the key lock cylinder, while doing this pull the ignition switch out of the ignition switch housing.

Installation

1 Insert the new key into the new ignition switch and turn the key to the run position. Insert the new ignition switch into the ignition switch housing. Wiggle the switch back and forth until the actuator pin mounting hole is aligned and falls into place.

2 Install the electrical connector back into the connector housing by pressing it in with your hands.

3 Place the steering column covers back onto the non tilt steering wheel and insert mounting screws. Tighten screws using a Philips screwdriver. Place the steering column covers over the tilt steering wheel and press the upper and lower portion together to snap covers back into the mounting plate.

4 Pull on the ignition key to ensure switch is locked into place. Turn key to the "off" position and remove the key. Insert the key and start the vehicle.

hope this helps you

The ignition key cylinder in a Buick unlocks the ignition and allows the Buick's engine to start. The cylinder contains a switch on the end of it (inside the cylinder) that sends an electric signal to the starter motor. When the ignition key cylinder fails, the Buick won't start. When this happens, you'll need a new ignition cylinder. Purchase replacement cylinders from Buick.
Difficulty: Moderately Easy
Things You'll Need:

• Ignition key
• Punch pin
• Cross-point screwdriver

1. 1 Remove the screws on the bottom of the steering column on your Buick. These screws hold the steering column cover on. You may need to tilt the steering wheel to its highest position to access these screws.
   
2. 2 Turn the ignition key to the "II" position in the ignition cylinder.
   
3. 3 Slide the punch pin into the access slot on the bottom of the ignition cylinder.
   
4. 4 Push the pin all the way into the access slot while you pull the ignition cylinder out of the steering column.
   
5. 5 Insert the new ignition cylinder into the steering column with the key in the "II" position on the cylinder.
   
6. 6 Push the cylinder into the column until it "clicks," indicating that it is locked into the column.
   
7. 7 Turn the ignition key to the "Off" position.
   

1. Disable air bag system.
2. Remove steering column shroud by removing self-tapping screws. Remove tilt lever if equipped.
3. Remove instrument panel lower steering column cover.
4. Disconnect ignition switch electrical connector.
5. Rotate ignition key lock cylinder to RUN position, then remove two screws retaining ignition switch.
6. Disconnect ignition switch from actuator.
7. Reverse procedure to install, noting the following:

1. If necessary, move switch slightly back and forth to align mounting holes with column mounting holes.
2. Activate air bag system.
3. Ensure proper operation of ignition switch in all positions.

FIRST OF ALL, TURN OFF RADIO,DISCONNECT NEGATIVE BATTERY CABLE. IF EQUIPPED WITH TILT STEERING COLUMN,REMOVE TILT LEVER.CAREFULLY REMOVE THE UPPER AND LOWER STEERING COLUMN COVERS. REMOVE THE 3 TAMPER PROOF TORX IGNITION SWITCH MOUNTING SCREWS USING SNAP ON TOOL TTXR15A2 OR EQUIVALENT. GENTLY PULL THE SWITCH AWAY FROM THE COLUMN AND REMOVE THE 2 ELECTRICAL CONNECTORS FROM THE IGNITION SWITCH. WITH THE KEY IN THE LOCK POSITION, DEPRESS THE KEY CYLINDER RETAINING PIN FLUSH WITH THE KEY CYLINDER SURFACE. ROTATE THE KEY CLOCKWISE TO THE OFF POSITION THE KEY CYLINDER SHOULD NOW BE UNSEATED. ROTATE THE KEY CYLINDER COUNTER CLOCKWISE BACK TO THE LOCK POSITION, AND REMOVE THE LOCK CYLINDER. ( TO INSTALL ) CONNECT THE ELECTRICAL CONNECTORS TO THE IGNITION SWITCH. BE SURE THE CONNECTORS ARE SECURELY LOCKED IN PLACE. MOUNT THE IGNITION SWITCH TO THE COLUMN 3 SCREWS FOR VECHICLES WITH THE TILT STEERING COLUMN THE SHIFTER MUST BE IN THE PARK POSITION AND THE PARK LOCK DOWEL PIN AND THE COLUMN LOCK FLAG MUST BE INDEXED BEFORE THE SWITCH IS INSTALLED. PLACE SHIFTER IN THE PARK POSITION. PLACE THE IGNITION SWITCH IN THE LOCK POSITION. THE SWITCH IS IN THE LOCK POSITION WHEN THE STEERING COLUMN LOCK FLAG IS PARALLEL TO THE IGNITION SWITCH TERMINALS. POSITION THE PARK LOCK DOWEL PIN OF THE IGNITION SWITCH SO IT ENGAGES THE STEERING COLUMN PARK LOCK SLIDER LINKAGE. APPLY A LIGHT COATING OF GREASE TO THE PARK LOCK DOWEL PIN AND THE COLUMN LOCK FLAG. POSITION THE IGNITION SWITCH AGAINST THE LOCK HOUSING OPENING ON THE STEERING COLUMN. BE SURE THE SWITCH PARK LOCK DOWEL PIN ENTERS THE SLOT IN THE PARK LOCK SLIDER LINKAGE INSTALL THE RETAINING SCREW AND BRACKET. TORQUE THE SCREW TO 26 INCH LBS. INSTALL THE STEERING COLUMN COVERS AND THE TILT LEVER IF REMOVED. WITH THE KEY CYLINDER AND THE IGNITION IN THE LOCK POSITION INSTALL THE KEY CYLINDER INTO THE SWITCH UNTIL IT BOTTOMS. RECONNECT THE NEGATIVE BATTERY CABLE AND THE CHECK THE IGNITION SWITCH FOR PROPER OPERATION OF HALO LIGHT SHIFT LOCK IF EQUIPPED AND COLUMN LOCK.ALSO CHECK FOR PROPER OPERATION OF THE IGNITION SWITCH ACCESSORY, LOCK OFF, RUN AND START FUNCTIONS.

CAUTION Disconnect and isolate the negative (ground) battery cable. This will disable the air bag system. Failure to disconnect the battery could result in accidental deployment and possible personal injury. Allow the system capacitor to discharge for two minutes then begin air bag system component removal. To install:

1. Engage the electrical connectors to the ignition switch and make sure the switch locking tabs are fully seated.
2. Before attaching the ignition switch to a tilt steering column, the transmission shifter must be in the PARK position. Also the park lock dowel pin and the column lock flag must be properly indexed before installing the switch as follows:
   1. Place the transmission shifter in the PARK position
   2. Place the ignition switch in the LOCK position. The switch is in the lock position when the column lock flag is parallel to the ignition switch terminals.
   3. Position the ignition switch park lock dowel pin so it will engage the steering column park lock slider linkage.
   4. Apply a light coating of grease to the column lock flag and the park lock dowel pin.
3. Place the ignition switch against the lock housing opening on the steering column. Ensure that the ignition switch park lock dowel pin enters the slot in the park lock slider linkage in the steering column.
4. Install the retaining bracket and ignition switch mounting screws, then tighten the screws to 22-30 inch lbs. (3-4 Nm).
5. If the vehicle is equipped with a tilt steering column, install the tilt lever.
6. With the key cylinder and the ignition switch in the LOCK position, insert the key cylinder into the ignition switch until it bottoms.
7. Insert the ignition key into the lock cylinder. While pushing the key cylinder in toward the ignition switch, rotate the ignition key until the end of travel.
8. Install the retaining screw into the bracket and lock cylinder. Tighten the screw to 22-30 inch lbs. (3-4 Nm).
9. Install the steering column covers, then the tilt lever, if equipped.
10. Connect the negative battery cable.
11. Check for proper operation.

this is the oldest info I have. should be similar

Section 11-05: Steering Column Switches 1994 Town Car, Crown Victoria/Grand Marquis. Workshop Manual
REMOVAL AND INSTALLATION Ignition Switch Removal

1. Disconnect battery ground cable. Remove the upper steering column shroud by removing the four or five self-tapping screws. Remove tilt steering column lock lever (if so equipped).

1. Remove lower steering column shroud.

1. Disconnect the ignition switch electrical connector.

1. Rotate ignition switch lock cylinder to the RUN position.

1. Remove the two screws retaining ignition switch.

1. Disengage the ignition switch from the actuator.

Installation
NOTE: A new replacement ignition switch assembly will be set in the RUN position as received.

1. Adjust the ignition switch by sliding the carrier to the ignition switch RUN position.

1. Check to ensure that the ignition switch lock cylinder is in the RUN position. The RUN position is achieved by rotating the ignition switch lock cylinder approximately 90 degrees from the LOCK position.

1. Install the ignition switch into the actuator. It may be necessary to move the ignition switch slightly back and forth to align the ignition switch mounting holes with the lock cylinder housing threaded holes.

1. Install retaining screws. Tighten to 5.6-7.9 Nm (50-69 lb-in).

1. Connect electrical connector to ignition switch.

1. Connect battery ground cable. Check ignition switch for proper function, including START and ACC positions. Also, make certain that the column is in the LOCK position.

1. Install upper steering column shroud.

1. Install the lower steering column shroud and tilt steering column lock lever (if so equipped).

Not an exact solution, but perhaps information that might lead to one.

1.Replaced the tumblers? I believe I would replace the entire ignition switch this time. It's my belief that the body of the ignition switch is worn inside, and will keep damaging the tumblers.

2.Do you have a tilt steering wheel? It's best to keep the steering column in straight line when starting the car, then tilt the wheel to where you want, after the car is started. When the steering column is in a tilted position, it puts undue strain on the ignition key switch, and the mechanism the ignition key switch operates, on GM vehicles.

This mechanism, consists of a half moon gear on the ignition key switch, that turns inside a 'Planetary' gear. I used the term 'Planetary', as the gear shape is hard to describe. It resembles an oblong loop, shaped like the number 9, with gear teeth on the inside bottom of the loop. This 'Loop' rotates, when the gear teeth of the ignition key switch, engage the teeth on the loop, and pushes a rod, or retracts the rod. The rod goes down the side of your steering column, and turns on, or turns off an ignition switch, located at the bottom left side of the steering column.

Having the steering wheel tilted, puts a strain on the ignition key switch internals, the oblong loop can break, and/or gear teeth can be stripped off.

Removal

1. Disconnect battery ground cable. Remove the steering column shroud by removing the four or five self-tapping screws. Remove tilt lever (if so equipped).

1. Remove instrument panel lower steering column cover.

1. Disconnect the ignition switch electrical connector.

1. Rotate ignition key lock cylinder to the RUN position.

1. Remove the two screws retaining ignition switch.

1. Disengage the ignition switch from the actuator.

Installation

1. Adjust the ignition switch by sliding the carrier to the switch RUN position. NOTE: A new replacement switch assembly will be set in the RUN position as received.
   

1. Check to ensure that the ignition key lock cylinder is in the RUN position. The RUN position is achieved by rotating the key lock cylinder approximately 90 degrees from the LOCK position.

1. Install the ignition switch into the actuator. It may be necessary to move the switch slightly back and forth to align the switch mounting holes with the column lock housing threaded holes.

1. Install retaining screws. Tighten to 5.6-7.9 Nm (50-69 lb-in).

1. Connect electrical connector to ignition switch.

1. Connect battery ground cable. Check ignition switch for proper function, including START and ACC positions. Also, make certain that the column is locked in the LOCK position.

1. Install instrument panel lower steering column cover.

1. Install the steering column trim shrouds and tilt lever (if so equipped).