If you're putting in the 440-6, I would also install the vapor separator by the fuel pump, the extra 1/4" return line, the 3/8" pickup, and the 3/8" fuel line. I would then add the little nipple to the top of the fuel filler tube then run the vent line into the rail just like stock a stock 70. A vented cap allows air in but not out through it's one way valve. The pressure has to go somewhere. If you install the vent, fuel and vapor can exit there before forcing it's way past your gas cap seal, then running down your paint.
BTW, my car has Urethane paint with hardener in it. Fuel doesn't hurt it if it burps out the side.
