I run electrics in both my trucks. A holley red in one, carter in the other. Both are pre-set for 7.5psi, which is perfect for a holley and dosne't require a regulator. I still use one though
On my 79 with a carter it likes 5psi so I needed the regulator for that. No return line is needed. I just installed the pump by the tank, and hooked it up to the stock fuel lines on the truck. The regulator I installed on the fender, passanger side.