Use a large easy-out (screw extractor) to hold the metal insert in place and use a socket on the other side...If they turn with the socket as you loosen them, they cut into the paint.
If they are not overly tight, a wood dowel-rod pushed into it may hold it from turning in place of the easy-out.,
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Large, easy to read and trace schematics with part numbers, wire colors, wire gauge, fuses, and electrical upgrade information. Trouble-shooting and replacement part numbers for those roadside repair adventures.
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