I don't know if a scotchbrite pad is tough enough. Probably hit it with 400 grit, prime it with a couple coats of primer-filler and block sand it with more 400 (wet this time--lots of water). Then prime it again and hit it with 1200-1500 wet. Then it's ready for degreaser (degreaser after every time you touch it with your hands and before the next coat of whatever), tacking, sealer, paint and clear.
