BlueJay,
Sorry it took me soo long to reply.
I had to drill and put 3 rubber grommets in the bed of the truck, one for fuel line, one for return line and one for the breather line. I got a fuel pump from Napa ($26) and a shutoff valve($40) to control 2 tanks, I plugged the line on the switch that was open when the switch was off, this way it only flow fuel when the pump and switch is turn on. The reason I put the shutoff valve in, is because the fuel was being siphoned into my stock tank. I wired it in-line with the pump, so when I turn on the pump it opens the shutoff valve and lets the fuel flow. I also installed an in-line filter and a manual shutoff before the filter and pump, this way I can turn the siphon effect off to change the filter or pump. I drilled and tapped a new hole and used JB Weld to secure a new fitting in the top of my stock tank in order to fill it. I run a hose from the breather fitting on the top of my stock tank back to the auxiliary tank, for overflow. I have a switch that lights up when on, in the cab to transfer fuel from the auxiliary tank to my stock tank. I just use my existing fuel gauge, and when I see I getting low on fuel, I just turn the switch on.