Related story. Around 1995, I had to kick a car out of our GAS STATION. Around closing time, I stopped in to check on things, and I saw a tubbed S-10 parked about 10-15' from our pumps. I asked the guy working, "cool, what's that guy doing?"
"I dunno. He asked to borrow a propane torch."
I ran out, and sure as shit, his blue bottle was mostly carbon-colored by then. I asked if he had a gauge. He said, "nope, you can't heat them up too much."