No start

Truck listed above is a 1989 C1500. So, I find this truck in the woods and we pull it out and tow it to my buds house. Needed a new distributor so we put one on and it ran alright but backfired and shot flames out of the intake. Now after about 5 months trying to time it and get it to run right it doesn't want to start and if it does by some miracle it barely runs and definitely does not idle. We replaced spark plugs and wires and a fuel filter. We are getting good gas the fuel pump and pressure regulator work fine. We do not have a air filter or housing but I think it should still run without one. We also cleaned and replaced the gaskets on the fuel injectors and they have a good spray pattern. Starter was also replaced and a new battery was put into it. No clue why it hasn't started but i'm open to all ideas.