RE: McCoy diesels
William,
I agree, it's always a good thing when you don't scratch a cylinder muff. Sounds like you come up with whatever you need.
I like to put "Stuck" engines on a 60 watt light bulb for about 15 minutes to loosen up the gook and then you can give them a shot of Marvel oil to keep them free.
Heat will sometimes loosen a muff too.