[72HuggerK20]

The reason for unhooking the ground on the battery is to break the circuit. Otherwise, a MIG welder typically running at around 19-22 volts when welding sheet metal will probably fry your ECM. Another thing that works is a service minder, but those are expensive and don't do any more than simply unhooking the battery. As far as spark protection, You can get a roll of 3M "spark paper", which is actually pretty great stuff, but it ain't cheap. Or a bunch of leathery welding blankets wrapped around sensitive parts is great too. I was just suggesting tape so that sparks have less of a chance to melt through the filler neck. You make a good point about the vapor possibly igniting. I still would highly highly recommend taking the bed off in the driveway, and then carrying it into the garage where you're working and set it on a couple sawhorses or something. They aren't heavy at all. Maybe 300 pounds at most. Once you have it off, you'll be glad you do.