2002 Z28, 2nd new fuel pump no pressure
 

Had 2lbs fuel pressure at the rail. Replaced the pump, I thought a no-brainer,well still same pressure. Installed 2nd pump same results of pressure again. Check voltage to pump OK, checked the ground OK, removed the relay and jumped with wire to run pump continuous. I can hear the pump run. Broke connection at filter into a pan, very low pressure. Engine will fire on the 2 psi but won't run so I have fire.
Is there a pressure regulator at the tank as I do not see one at fuel rail.
Learned on forum that oil pressure switch is somehow involved. Where is it located? and can it be jumped to eliminate it to test?
I am a new member from Alabama and fairly handy around cars but this has me stumped. Please help or provide me with a few fresh ideas.