Chuck. There is not much you can do. You can strip the one panel and replasticoat it. In time the new paint will blend in with the old, in appearance. If you polish the metal, it won't ever match. If you use 0000 steel wool, very gently, it will take the oxidation off, but it will change the grain of the metal, to the extent of not matching at all, as you look at it from different angles.
Best you can do is refinish that panel, and don't look at it for awhile.
You know the old saying, out of site, out of mind.