I bought a new RCI aluminum fuel cell on e-bay, to mount in my pickup bed. It has three -8 AN male fittings. One fuel out, one fuel return, and a vented(?) antirollover valve. My plan is to cap the fuel return, since the stock tank doesnt have a fuel return. Should I run a line from the threaded vent port underneath the truck, and is it truly a vent for pressure equalization in the tank?