This Gretsch Electromatic suffered a fall right on the output jack which pushed it straight through. I decided to install a metal jack plate to cover the hole. It is tempting to just screw the plate on but the thin walls of the body don’t provide mush support and the plate would likely come loose over time, or worse, get pulled of by accident. To increase the strength I made up a curved piece of plywood using maple veneers and glued it inside. The jack is installed from the inside so the plate is held on by the screws and the trhreaded barrel of the jack.