91 S-10 2.5 to 2000 S-10 4.3

I am having trouble with a conversion. I swaped a 2000 4.3 into a 91 s10 which had a 2.5. I went from manual to auto trans too. I had the harnesses spliced together by a reputable company in Texas and had a reputable company from Oklahoma that specializes in PCM's knock out the VATS codes. However, I cannot get the truck to run. I have excellent spark but no pulse to the injectors. I replaced the fuel pump with one from a 91 typhoon or syclone and have over 55 lbs of pressure too. The harness was sent back to be checked and they said it checked out fine and the computer was run in another truck which I heard run. They put it in a v8 and 6 cylinders ran. The wiring company seems to think I have a bad ignition and has given me an external ignition back with the harness. While I have not had time to try it yet, I am doubting that this will work. Does any one have any suggestions why I would not get pulse? The distributor is installed properly and is good with a new cap and rotor, it has new plugs and wires, the coil is good, the cam and crank sensors both have the proper resistance, it has fuel at over 55 lb at the rail. I just don't know where to look next. Please chime in with any suggestions. Also, I forgot to mention that it will run for a few seconds with carb cleaner or fuel in the throttle body.