we did a engine swap from a 1996 4.3 v6 to a 1997 5.7 v8 changed harness, computer, crank sensor, distributor, ignition module, turns over good, have a good spark through the coil wire but no fire to the spark plugs and I need help no one so far has not been able to tell me what to try next so I can get this to start been trying for 3 months now, any help is greatly appreciated and thank you in advance.

 

Being that you changed the distributor and crank sensor, did you perform a crank relearn yet? Need a programmer that can do it.

 

where is a good place to get one of those

 

Dealer can do a crank relearn, or someone with one of the obd II programming software systems.