Bob Bonto (tech advisor in the ROA for 71-73 Riv's) reccomended to me once to use DWG PREMIUM METAL POLISH. It's a waterless wash type stuff from Dri Wash 'n Guard It's down the page a bit here: https://www.mydwgint.com/cart/DWG_Shopping_Cart.asp Worked beautiful on my bumpers. (And I even polished my silverware with it on rainy days when I was terribly bored). BUT, anyway.. I think it's a great product, and my bumper is not the best specimen at all. I'm just angry that I left it behind when I moved out of my last house!!! I forgot a couple things, but I think I miss my Dri-Wash the most! This is their description of the product: DWG PREMIUM METAL POLISH Polishing metal has never been easier! DWG Premium Metal Polish makes short work of polishing silver, chrome, brass, gold, stainless steel, platinum and other unpainted metal surfaces. DWG Premium Metal Polish works wonders cleaning a wide variety of unpainted metal surfaces. Just as DRI WASH ‘n GUARD® cleans, seals, polishes and protects painted metal surfaces, DWG Premium Metal Polish cleans, restores, and protects unpainted metal surfaces. Simply rub onto the metal surface, allow it to dry, then buff off lightly. It’s that easy! You can then seal and further protect the surface by applying DWG for the Car or Home. DWG Premium Metal Polish is great for: • Mag wheels and chrome bumpers • Decorative brass • Tanker trucks and external fuel tanks • Airplanes, metal canoes, and fishing boats • All the unpainted metal surfaces around your home! Use DWG Premium Metal Polish for polishing and protecting unpainted metal surfaces!