1988 Ford Bronco engine stallin out when engines hot!

When im driving down the road about 15 mins after I fire it up the trucks oil pressure drops really low and the engine light comes on and it starts to spit and sputter I just replaced the following: spark plugs and wires, fuel regulator, distributor module, fuel relay, fuel filter, distributor cap, rotor button, alternator. I ran fuel injector cleaner threw it.

the fuel rail pressure rail was at 13.5-29 psi and it fluctuated and stalled then cut off

what could the problem be please help