Okay So the problem began with the truck stalling out and the fuel pump and fuel system failure of both pumps in tank and the fuel pump inline and the regulator / tank selector. I replaced both in tank fuel pumps , the inline pump and the regulator and all the lines . The original owner bypassed the fuel tank selctor and had it rigged to run in an unsafe way . The truck wasnt getting fuel to even the front inline pump or the rail prior to my repairs . Now with key on you can hear both intank pumps turn on and the inline fuel pump kicks on gets fuel to the rail but the truck will not start. After replacing the pumps and fuel line the truck ran took it filled up on gas and parked it . Next morning the truck wont start . I checked the fuel rail there is fuel at the rail but it wont start. So next i shot some starting fluid into the intake and shre enough it starts and runs as long as you give it fluid so its not a spark issue .
Im thinking its possibly the fuel pressure regulator or fuel injectors that are bad I tested the voltage to the injectors and they are indeed getti g power . But the fuel pressure regulator was damaged there was gas in the vacuum lines so the diaphragm must be shot .
My question is am i on the right path or is there anything I could be missing ?

 

If gas is coming out the vacuum fitting on the fuel pressure regulator then replace it and test it. Another thing I would do just for craps and giggles is to pull the PCM and check the caps on it. Longshot there but it could be worth a look with all the new flooding of trucks with bad PCM's lately.