The tanks for a EFI are the same from 87-91. They come in 2 sizes, but Crew Cabs take a 20gal tank. You CAN put any 73-87 20 gal tank in it, but it won't have the baffling in the tank..
Why would you want to delete the intank pumps? Having them in the tank is a MUCH better/prefered design. It isolates the noise, and it keeps the motor cool, extending the life of the pump.
TBI's ran from 12-18lbs and was regulated to 12-13 at the TBI unit.