I wonder if Novus Plastic polish (three-step kit), which I've used in automotive applications, would help the finish. I'm about to remove, permanently, an Ofmega plastic RD from a project bike, maybe I'll test that out just for fun.
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Larry:1958 Drysdale, 1961 Gitane Gran Sport, 1974 Zeus track, 1988 Masi Gran Corsa, 1974 Falcon, 1980 Palo Alto, 198? Vitus 979. Susan: 1976 Windsor Profesional.