What would be the best route to strip a steel bumper of the exhisting paint to get it down to the metal to sand/primer and re-paint? I've been sanding it but that's taking long... would a heat gun work? I'm looking for a quicker way just to get the paint off... I need to do it cuz the bumper I got from the junk yard has some surface rust on it so I need to get all the paint off... then sand it all off and repaint it.. thanks!