Put down the silver can of spray paint. Re-skin it as a DIY project.
Degrease & clean with your favorite magic cleaner i.e. simple green, castrol, amway whatever.
Acid etch clean & brighten with Eagle One Mag cleaner <$8.00> product #?? http://eagleone.com/mag-wheel-cleaner
Note: (Heavy hand scrubbing WILL be required use scotch bright greenie or small wire brushes etc...) Multiple applications, as needed depending on how much grime or more likely alum (rust, I know non iron based metal) oxidation, pitting, mung, powder etc exists.
Washdown with clean lacquer thinner. Best done with a paint gun to drive out any remaining contaminates in the pores. Wipe down with clean cotton white cloth to remove any traped oils work quickly, the thinner evaps very fast.
Buff - Burnish the surface with a BRASS brush. (This is not polishing) optional, test a spot and see what the results are, i.e. do a back side or sample part till you achive results that are to your liking.
Seal-Skin with a 1:1 mix of PPG DX501 & cold water <$25.00> re.chromic acid based chemical that will produce a chrome conversion coating on aluminum DX501 is a clear version of DX503. The coating formed by DX501 is clear in color. It is used when it
is desirable to retain the silver white aluminum finish . Apply to the aluminum after the cleaning. Similar to anodizing is that it stabilizes the aluminum from the air and moisture. Stains also will clean up. Keep the manifold and valve covers looking cast appearance.
THe BEST method is to send to Jerry, but,,,,,,,,,,,,,,,,,,,and I have had many items skined & rebuilt and have had great service, you know you can not send every thing,,,,I would like to.
My sample picture was to big to post, I just did a Weiand Maifold that turned out very nice.