Then I use a "surface preparation" pad on a die grinder to remove paint and expose the spot welds. For the type of spot weld bit I have, I first use a small bit to drill a pilot hole, then the spot weld bit to cut through the upper layer of metal. You can usually tell when you've cut through by feeling a little more give, and rust and dust start coming out of the hole while you are drilling. Then a screwdriver to pry the cut out portion loose, and voila, the bad part is off. BUT WAIT!!! Behind that is another chunk of metal that looks just as bad as what I cut off (story of my life on this build
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