Been waiting a few weeks for a fuel pressure gage, Amazon lost one chased it for days and then sent me another one. In the mean time I have been educating myself on how the system actually works, it's not Rocket Surgery but it's not as simple as it seems either. Already replaced both fuel pumps with after market junk that may yet be replaced again with stock units. Replaced the fuel pressure gage, third one was the correct Delphi unit at least as far as fit goes. Nothing changed at all the pump still ran thirty minutes before shutting off at which point the truck would start and run normally. I had incorrectly assumed it was fuel pressure that shut off the pumps, wrong. RLA told me from the start it was the ECM but I had to understand for myself how and why that was true. It seems that as long as the clock circuit is enabled the injectors are disabled, it would start with starter fluid but not continue to run. But then again that's only a guess since the ECM is known to be faulty at this point.
I spent money and time that wasn't necessary by not taking the time understand how the system works and what the symptoms actually meant, lesson learned. I have a refurbished pre programmed ECM on it's way. I don't think this is the end but it should get the truck running, The gage is only reading 50 PSI instead of 65. So it is either the wrong fuel pressure gage or the pumps I bought are junk. I will keep working on it until it works as intended.
Thanks to everyone for the help, after this is solved there are many other issues to address. So more annoying questions to come!

 

Could be wrong fuel pressure regulator, if you got like below pic, see the operating pressure of 47psi, not enough.

 

Put the old fuel pressure regulator back in gage now reads 62 PS! so clearly the one I purchased was not the right pressure. Checked it with the hand vacuum pump and saw the fuel pressure dip as I applied vacuum and the vacuum held so it is working as intended.