Remove pitting from board racks & speaker cans?

Anyone know how I can get my aluminum board racks and speaker cans back to their show room shine? The previous owner left the boat on a lift, in the elements. I have tried using a buffer and some polish which starts to bring the shine back but doesn't remove the excessive amount of pitting. I know I am going to have to resort to harsher measures, but don't want to ruin them with experiments! Anyone have similar experience with this problem? I have emailed Roswell (the manufacturer) but haven't received a response yet.

.....yeah I use peek polishing compound and my finger inside a cloth.......you have to rub extremely fast back and forth for it to be really effective (if you even just rub at a good pace...it wont be fast enough) ......needless to say it is back breaking work.......I just do a little at a time over the winter.

If they are chrome you can forget it. If they are aluminum you're OK. Those mothers buff balls work pretty good with cord 120v drill.

that is what I was dreading! I was thinking about using something more abrasive or a polishing wheel on my grinder. I really don't want to have to buff it out by hand!