Hey guys, thanks for the reply.
Mission is half complete. The Big Dot came off with heat from the torch. I slightly melted the plastic insert, but it's still working and glowing. It even appears that I can reuse it.
Just like you said, the solder melted when it got a dull red, and I pulled it off with a pair of vise grips. I'm debating about cleaning the bottom of it and reinstalling it with Black Max Loctite instead of solder. Should I just go with the solder? I'd have to get another container of MAPP gas, when I took off the torch head, it started leaking. I'd also rather not refinish the barrel, as I have no way to do so.
I did the cut very carefully with a hacksaw and then dressed it with a file. Looks pretty good, I'd love some recommendations about how to refinish the end though, I guess whatever product is equivalent to AlumaBlack, but for steel.