I have a tank sending unit, out of a station wagon i believe, that has the second outlet (inlet) for a return line. Currently is plugged. Would i benefit from installing the return line? I am also running an elec. pump that's in the back, in front of the gas tank, slightly higher then the tank, with the mechanical pump. (elec. has a disconnect switch just in case.) I'd have to change the std. mechanical fuel pump (it,s new :ball, Almost ready to stick in the new motor, or so i've been telling the wife for a year. Any thoughts? Thanks, Rick