1986 rx7 starts then dies
 

Hello everyone, new to rx7's, not new to cars.
I traded a beater 1995 miata for a 1986 project fc rx7, the car is way cleaner than the miata and had less miles (I know that doesn't mean much for rx7's), I knew the car was in a non-driving condition when I bought it and I took the guys word for it that it ran. I trailer the car home and put the battery on a charger because it was totally dead. After it took 2 days to trickle charge, I put it in the car and cranked it over. After discovering a massive exhaust leak I realized the fuel in the car was junk, I mean it was brown. The car would chuckle a little bit with that fuel but I knew the tank was almost empty so I pumped the rest of it out and put in 5 gallons of fresh 93.
The car then tached up to 3k and would then choke out, it would pop and backfire if I tried to give it gas and keep it alive. I then started to look for vaccum leaks and discovered that the IACV hose wasn't clamped on. I also tightened the spark plugs because they were hand loose and examined the plug wires (all plugs and plug wires look to be brand new, spark plugs were wet with gas and not fouled). The car would then start with the vaccum leak fixed and would tach up to 2k this time. After reading online I decided to check the afm spring and plug, all seemed fine here. Car would continue to do the same thing. So I had fuel, air, and I assumed spark, but most likely at the wrong time.
So after checking what seemed like the basics I decided to examine the issue further, I actually was able to move the car into my garage because it wouldn't die above 2-2.5k. So that brings me to today, my train of thought was because the car did have an 88 motor put into it maybe the primary injectors weren't plugged in, because it seemed like the car ran when the secondary injectors might be in use. I pulled off my upper intake manifold and they all seemed fine, as of now I'm out of ideas and waiting on a new manifold gasket and primary rail spacer. Is it possible that both primary injectors are junk? I know the 88 NA injectors are different than the 86-87 na injectors but the car seemed to have 86 injectors in it, red top with the black body. What should I check next?

Like I said the car is an 86na shell with an 88 na motor, swap not done by me, car is all stock engine wise except for a K&N filter (Not done by me lol) and a racing beat exhaust