I am trying to find out if there is really a need for the fuel return line I have in my car. The reason I ask is because all the aftermarket mechanical fuel pumps ( Holley and edlebrock with a high flow rate GPH) come with the fuel in and out to the carb, not a return connection. I will need to go to a higher output pump with my rebuild and cant find a Mech pump that has the return line hook up so is there a need to have it and if not, I know I need to replace the in tank sending unit to a one line unit and if I remember correctly I will need a vented fuel tank cap? Thanks all in advance!