The time is another thing. Yes I said to soak it in fuel overnight, but most times I can free it up in a few minutes with a bit of fuel. But when really stubborn I fill up the crankcase and cylinder and let it soak. If gunky on the outside I put it in a bowl of fuel. I prefer fuel because the oil will protect it from corrosion. I don't think leaving it in methanol overnight is an issue, but I have forgotten to pull it out for days on end. The oil neutralizes that problem. Methanol is corrosive to aluminum and its not just the moisture trapped in it.

For me the crockpot is for really messy engines with burnt castor. Good point on the antifreeze fumes. I believe methanol fumes to be not so poisonous, God knows I have inhaled a lot of methanol fumes and OK so far. Hmm wonder if it causes some minor insanity? Might be why some of these threads are so wacky. I have inhaled a bit of antifreeze fumes as well but heating it intensifies the amount of fumes, the cover seems to let some escape.

BTW I have accidently gotten a small amount of antifreeze in my mouth and it tastes better than it smells, like a candy syrup.