I've always heard that power tools can degausse pickup magnets, but other than some vague internet references, I've never seen it happen. However, having now had my first experience with a degaussed pickup - received it that way, ugh - I'm wary about using power tools too close to my pickups. Say you want to rout a cavity for a neck pickup or a string ferrule block - do you strip the body first? What about when you're using a cordless drill or a rotary tool? Just looking for common/safe practices, I guess.