Personally, I think that if the aluminum part is not anodized from the factory to start with, you can polish it to a flawless mirror finish and it will be "correct"....or even better than just "correct"!! Heck, if you decide that you don't want the high polish look later, just wait a (could sometimes be a long wait though depending on what conditions you ride and store the bike in) while and it will dull up by itself over time to look closer to what you started with.
JMO.

Chombi