Don Jr-what I am trying to get off is a bolt with a short threaded head and nut(something like a 1/4-20) that holds the ground for a CPI and then the bolt is one of the two bolts that holds down the thermostat housing.Of course that would get very rusty.Without even touching it the nut was in bad shape and I spray the heck out of it and blew it off.Just one more dumb GM design.Hard to get any heat on it because of tight quarters and the ground wires.I'll try you suggestion.Only other thing I could think of is to take a chisel to cut steps in the nut to try to spin it off.And yes pound on a junk socket.