In tank fuel pumps and gas fillers questions.

[Yellow Cheyenne]

I am planning to put a gas tank from a 87-91 suburban in my pickup. I may also sometime in the future install a TBI or TPI and would like to prepare now when it is easier. If I install the in-tank fuel pump, does it need any computer stuff to run it? I notice on newer vehicles that have FI, the fuel pump will run for a few seconds and then stop when the ignition switch is turned to the on position. Is this few seconds of run time determined by a computer or does the pump build up pressure and then shut itself down when the pressure gets to a certain level?

Also, the point that I am planning to install the fuel filler neck is only about 2-3" above the top of the tank and the fuel filler tube will be about 18" long. Is that enough of a drop to allow efficient fuel filling or will I be at the pump for 20 minutes trying to refill the tank?

Thanks in advance for any assistance.