[PepperTreeGarage]

I have that same tank. The far single vent is capped off. I didn't need a return line. The larger one of the two goes to the filler neck. Vents air out while filling. On the other one I put an anti-roll vent. This vent is needed for when the engine draws fuel. Lets air into the tank to replace the fuel that is being used. Subsequently, I didn't like the vent being outside my filler box. It is now inside the box out of view. Don't forget a filter. I put mine in the frame rail under the cab where the new hard line from the rear tank meets the old line from the in cab tank. Hope this helps. Good Luck.