[mr48chev]

If you are going to take it down to the bare cases I'd use Grease Eater to clean therio cases and then replace the rear bearing and reassemble the alternator.

I've thought about using either McGuire's or Griot Garage aluminum wheel cleaner on a set of spare cases to see what they look like too.

I wouldn't use a wire wheel on the cases as it will mar the finish.

I've got a stack of old alternators here that are headed for the rebuilder as cores or to the scrap yard in a few days so I might play a bit at cleaning up a couple of cases to see what happens.