As you are finding out aluminum and salt air don't mix. Have you tried a green Scotch Brite pad? No matter what you do, It is going to take a lot of elbow grease and time to clean your window frames. After you get them cleaned and polished I would suggest taping them off and spraying them with a clearcoat of Krylon Crystal in a rattle can. That should preserve your work for a while.
Carl, Elaine & Finn The Beagle
2006 30' Classic W Slide & Limited Package Katarina
2006 GMC 2500 HD 6.6 Turbo Diesel Crew Cab 8' Bed
NQ3U (was KB3UOM)