3. With the bumper hung, it was time to tackle the 14-plus impact-strip holes. To get a professional's guidance on the proper way to fill holes in a bumper, I went to Eightball Rods and Choppers and sat down next to Martin Lange. Martin is a sheetmetal guru, and I pulled him away from a bitchen '32 Ford coupe for my little bumper project. The first thing Martin did was pattern little filler pieces out of flat stock the same thickness as the bumper.