let us say it's anodised (I'm doing some stuff soon that I would like to be polished, not just raw.)
If the part is anoed then there is a few ways you can strip it, The best way I have found is dollar store oven cleaner. spray the part let it sit for no more than 15 min and scrub the hell out of the part with fine steel wool and then rinse the part and repeat until the part is a dull raw color similar to this.
********Be careful not to leave the part in the oven cleaner too long because it can cause the aluminum to start to pit .
and then use some kind of polishing compound and a buffing ball or a rag.
you can keep polishing with the compound as much as you want.
This was my end result. but I could have kept on with the polishing but I was lazy and quit.
I even did the bolts and cones.