97 350 vortec will not get fire

consider substituting the ECM and checking all of the electronic harness connections

check the ECM

Is coil firing? Ignition leads faulty!

There is not really a negative primary coil wire per se BUT ...............

The 2006 carbureted models have a three wire 83B connector with #3 wire being BE/O Front coil wire carrying the primary current supplied from the #2 W/BK wire to and through the front coil primary circuit to the ECM (#2 wire being W/BK and supplying current from the Stop Run Switch to both front and rear coil primary circuits at the same time) and the #1 wire being Y/BE Rear coil wire carrying primary current supplied through the W/BK wire to and through the rear primary wire #1 to the ECM. So, current comes to both coil segments (front and rear) simultaneously, passing both primary windings by two separate wires to ground through/in the ECM until the ECM opens each circuit independently of the other and thereby collapse the current in each primary winding into each secondary winding at the appropriate time to fire the respective spark plug.

The 2006 EFI models have a four wire 83B connector with wire "A" being Y/GN Power supply wire; wire "B" being GY/BE and the ION sense wire to the ECM; wire "C" being Y/BE Rear primary coil segment and Wire "D" being BE/O Front primary coil segment. Again current comes to the coil through the Y/GN "A" wire and passes through the front primary circuit to the ECM via the BE/O wire until the ECM opens the circuit which collapses the front coil primary current into the front coil secondary circuit inducing a high voltage current which then bridges the gap and fires the front spark plug and through the rear coil segment primary circuit to the ECM via the Y/BE wire until the ECM opens the circuit which collapses the rear primary current into the rear secondary circuit inducing a high voltage current which then bridges the gap and fires the rear cylinder spark plug.

I hope this answers your question whichever 2006 Softail model you have.

Check to see if the spark is strong with a spark tester if it is replace the spark plug wires

Check the plug wire from the ignition coil to the distributor cap.
If you haven't already, replace the distributor cap and rotor.
The GM Vortec's have issues with moisture getting inside the cap and rotor and causing problems.

I’m happy to help further over the phone at https://www.6ya.com/expert/jason_00b31cc8f593773a

Follow your coil wires back to the connectors for the ECM the wire could be corroded from cutting insulation to check previously or the coils connector check for continuity of the wires all the way back to the ecm

Right at the coil is the ICM (ignition control module) These wire are known for poor male to female connection have some one crank it and you wiggle it to make contact,Also where the battery is is a power ground if that ground is corroded it will give code P1355.

Bad ECM

po300 is random misfire detected from the ecm. could faulty spark plug wires or coil causeing the problem. also check spark plugs as well. use a inline tester to check fire from the coil to plugs. if fire from coil is good on each plug then change the plugs. hope this will help you!!!!