I've used them. They really do work. I got the pair shown above from Eastwood. Really only need the smaller one. Just move it more. I was also tipped by someone here to use a piece of copper pipe. You can cut it and hammer flat. Handy for getting into tight spots. You just have to figure a way to keep it flush with the backside. I use magnets for that. You can find those wherever you find the copper plates.
Dennis
