Sorry I'm so late to the punch, but I recommend Adam's Metal Polish #1 and #2, as Assassin mentioned, to restore aluminum, chrome and SS. Hands down the best metal polish I have used. I have pretty good collection at the shop, from Mothers to all those no-name products you see at shows.
Obviously, it is unable to repair pits in chrome, but it will work the pits to a point where they are less noticeable.
Pretty good video of Adam showing how to use the products:
Adam's Metal Polish 1 & 2‏ - YouTube
Once you've restored the metal, protect it with a product like Fukken Wax or Adam's Buttery Wax to prevent future oxidation. Adam's Brilliant Glaze really pops on chrome too!
Email me and I'll hook you up on the Adam's Metal Polish:
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