get a high speed grinder, air or electric and get some buffing wheels for em. i use an angle grinder hooked up to a compressor and ,BLUE MAGIC is the best stuff i've ever found out about. it's so strong that a frien d of mine left some on his tail pipe on his new dodge truckj and it ate the chrome off ! but it works great! so hit it with a buffer and a couple dif times then use a few clean rags on em.