Fuel is returning to my front tank while using the rear tank. Overflowing onto the ground around the cap, 5.8 liter . Thinking it's the selector. Problem is I can't find it. I have a dump body on the truck, and the bracing for the pump isn't really blocking anything, so if there is one there I would see it. Is it located on the frame rail behind the midship tank? I seen the pics of this thing and there is no way it could fit. Or being it's a cab chassis does the switch in the cab control the in tank pumps? On my diesel it's right there in plain sight. Anyone have any idea? thanks.