That turned out great. I don't think I have the patience for that, but there are other methods to achieve smooth surfaces.
I saw my friend's vapor-blasted engine, instead of texturing the aluminum like sandblasting does, it work-hardens the surface, and leaves it smooth. Grime easily wipes-off. He left the engine its natural color, it's a KZ1000. I didn't have my phone to get a pic, but it looks good in the bare aluminum finish. The shop owner wants to try the dry ice blasting, which also doesn't mark the aluminum. It looks like it does a great job of cleaning metal of whatever is on it.