Non-MOPAR tech question... My apologies!

If it turns out you have a leak make it easy on your self and take the bed off the truck instead of dropping the tank. unplug the tailight harness and disconnect the filler tube from the body. remove the bolts from the floor of the bed and put a saw horse behind the truck lift the body and move it back so it sits on the bumper and the saw horse. make your repair and put it back on.

Brian