I’ve seen a few use a cheap metal trash can with a turkey frier under it for moose. They cut channels on each side into the trash can so it goes low enough to cover the head.
If you use the galvanized tubs from the hardware store you can boil a few skulls at a time. I bought one of the basecamp single burners from walmart and a 20lbs bottle of propane. I have had mine for 4 years I think in total I paid $75 for everything.
Looks interesting. And worth a shot. It will be hard to do in MT over the winter though and i don't really want it in my garage. I suppose i could hang the heads in a tree somewhere over winter maybe.
Anyway, I'd still like the boiler setup for hunting in areas where CWD is an issue and you can't transport brains.
Just a PSA, be cautious when heating anything galvanized. The zinc fumes can be dangerous..... I use an old coleman camp stove and a chopped off steel drum. Slow simmer is plenty and helps keep from splitting bone. I know many need a fast way because of CWD issues, but IMHO maceration gives a much better end result.