Don't worry about fire down there, just keep a rag handy. Shouldn't take much to put a big slit in nut and blast it off with a hammer and punch. I assume you meant cutting torch not just heat. Heat won't help if you can't hold the head. Will the bolt withdraw or will it hit something?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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