i run an efi fuel pump with regulator and return on a carb and have no problems maintaining 6-7psi, same principle as yours i would imagine. return line, return line, return line. plus the fuel will stay cooler running back to the tank rather then sitting in the engine compartment if that is where the regulator is located. i'm using a generic spring style regulator btw, they usually have a bypass port located on the body somewhere.
it wouldn't be right if you weren't doing these things at the last minute you know
