Edelweiss

Hello to all-

My son was using the truck and he had an intermittent start condition for the last several days now we have a full-on no start condition. It would cough and run on snap start ether through the intake. Believed to be a fuel delivery problem I dropped the tank and put a brand new fuel pump assembly in. No start still.
It appears not to be getting any kind of priming signal as it normally does when you turn the key one click. I can't hear the pump at all even on the brand new one.
I move forward anyway and bench tested the old one hooked it to 12 volt source and it was fine.
I even replaced the oil pressure switch also no start still?
So, I went down this whole road for nothing as the old ones (oil pressure switch and fuel pump) appeared to be good, any ideas?