Lift supports 2003 Trailblaizer

Open the liftgate. Remove the liftgate applique. Refer to Liftgate Applique Replacement in Body Rear End. Remove the back up lamp socket (1) from the liftgate applique by turning the socket (1) counterclockwise. Remove the back up lamp bulb from the socket.
Lift gate Applique Replacement
Remove the lift gate trim panel. Refer to Lift gate Trim Panel Replacement .
1
Lift gate Applique Nuts (Qty: 5)
Tip
Disconnect the electrical connector.
Tighten
10 N?·m (89 lb in)
2
Lift gate Applique

depends on what model you are asking about . some of the rear lifte gate struts are bolted on . just remove the bolts while supporting the real glass or lift gate .And some struts use a little push clip at each end of the strut . these you can use a pick or a small flat blade screw driver to pop out of place . the new struts should have them already installed on them . so they just snap back on . just remeber to support the gate while changing the struts

They snap off,and snap on,the auto parts stores can order them if they do not already have them.

You will need to remove the interior panle from the loft gate to axess the latch
there is 4 screws along the bottom of the panle to remove then carfuly pull the panle away from the lift gate there is plastic clips that hold the panle to the gate these may need to be replaced when re installing the panle they can be purchased at the jeep dealer.
now look into the lift gate and you will see where the handle rod conects to the latch lift on this rod and the gate will open
to replace the handle remove the 2 10 mm bolts and disconect the rod from the latch install the new handle and rod to the latch install the 2 10 mm bolts. install the panle and 4 screws
this should cover it

If it is for the turn signal bulb for the tail light, here ya go:

Tail Lights

1. Open the lift gate.
   
2. Remove the screws from the tail lamp and pull the tail lamp from the body.
   
3. Disconnect the electrical connector from the tail lamp.
   

To install:

1. Connect the electrical connectors.
   
2. Install the tail lamp and tail lamp mounting screws.
   
3. Close the lift gate.
   

Tail lamp detail view

pretty easy to do find the ends of the lift support should have a clip on the back side of where it connects pull clip out and remove shock.

replace the lift gate/door ajar switches, they are located inside the tail gate on the left and right latch assemblies.

yes. there are 2 or 3 clips that must be somewhat forced out. so carefully, but forcefully pop the taillamp assy. out and change the bulbs.

I just want to know if there is any manual to disarm the lift gate and check for the problem. Currently my door is lock and cant open, how you force it to open?