glad you asked as i just finished a set last week. i use a small palm sander on the flats all the way thru 400 wet( i wet the part with a mist bottle. if you try this and shock yourself you are on your own)
as for the curved surfaces i do this by hand. as for the wheels you have i would shy away from the sisal it might be too aggressive for the soft cast alum. after you spend all the time to sand to 600, sisal is going backwards. try emory and spiral. best of luck bro. keep us posted on how it works for you.