Installing '88 454 in '72 Sierra Grande...Help

[72twotone]

Hey members, I recently purchased a 1972 GMC Sierra Grande that came with a 454 from a 1988 dually . The engine has the harness and computer from the truck. I want to keep the TBI setup but am confused with the proper fuel pump. My "Haynes" manual says that 1988-1994 7.4L engines require 26-32 psi and all of the treads that I have read say 13-16 psi is ok.
Also, I plan on using the '72 th400 transmission and was wondering if I will have any issues with the ECU?
Finally, what wires from the ECU will needed to be hooked up?

I greatly appreciate any help and will post pictures tonight