Here you go............
First off, if there is any type of paint or clear coat on the item, strip it with some aircraft stripper available from your local hardware store. Get the surface ass clean and rare material as possible.
Second. Sanding. This will be the hardest and most painstaking part. Start off with a rough grit to get all the rough casting down and smoothed out. For EVERY grit you use, sand until the scratches created by the paper are all the same. Move up a couple grits when you do. I recommend an electric sander for grits all the way up to 600. When you get to 600 grit, start by hand and sand again till all the scratches are the same. When you get to 800 grit, start to wet sand using either water or WD40 as your lubricant. Sand till scratches are all the same. For the best shine the aluminum has to be smooth. The smoother it is the more it shines. Go up to 2000 grit and stop.
Next, clean the rim thoroughly to get off water and wd40 you might have used.
Last but not least, buffing. To get the best shine I recommend getting a buffing kit like Wenol offers. It comes with wheels and compounds. Start off with a medium buffing wheel and Black Rouge (compound) Hit it up with that multiple times. You should be blingin' already. After that is done, take some White Rouge with a little softer buffing wheel and hit it up a few times.
Take a step back,
Considering your engine will come in contact with water you should clear coat it. Professionally if you can.
When your polished parts get dirty, use some metal polish like Wenol in the red tube or Top-Brite. Stay away from wheel polish and such.
BTW, The wheels and compound could be found at a auto parts store, or you may have to order online at Eastwood company or something. Or got to Wenol's site. Autozone I think may help you, I thought I found it in there once....