I have 1990 YJ converting to small block chevy. Any info would be helpful trying to figure out how to properly vent gas tank? Using electric fuel pump with regulator with return back to tank. Regulating pressure down for carburetor instead of fuel injection. I have been told I need to vent tank to keep tank from swelling. Would avented cap be good enough, or is there way to recirc pressure vapors back into system?