88 Bertone fuel issues - V-6

I have narrowed my starting issues down to fuel.The car was running great then one day it started up them immediatly shut down and would not restart.It's been hit or miss.If I waited 5-10 minutes it would usually start back up and run for a couple days then die again.It died while I was driving it,no warning, all of a sudden all the dash lights came and we coasted to a stop.Started up 1/2 hour later like nothing happened.I'm not sure exactly how the fuel system works or what parts are involved and in which order they come into play.Is there basic tests to see if it's electrical(a relay) or the fuel pump (without removing the pump)..lol
Or maybe some place online that I can find a schematic or manual for the 780 V-6 fuel system.Thanks much.