that's totally wrong. you never ever fill a hole w/ boddy filler. once moisture gets in behind the sheet metal, the filler will crack out and you'll get monster rust. if you want it done right, weld the holes, then use body filler. don't use fiberglass/resin because it expands & contracts @ different rates @ different temperatures than filelr and steel. don't cut the corners when it comes to your car's body.