Yeah man, not really hard to do, just alot of manual labor.
Basically, this is how I did it. First you need to sand off all the rough casting, which is the texture created when the pieces were made. To do this I used 80 grit sand paper. Use a sanding disk with a drill on the easy parts, then switch to a dremel with a mini sanding disk for tighter areas. Then finally you'll have to sand by hand the really tight areas and corners. Also, I didn't sand the underside of the intake manifold as it would never be seen. During this stage I sanded off the "16 Valve Dual Cams" off the valve cover for a cleaner look, plus it would've been a pain to polish in between those small letters.
When you finish with this step, repeat everything with 120 grit paper/ disks.
The goal of each sanding step is to remove the scratches and lines from the last lower grit paper. This is the key to make it look really good. Don't move on to 320 grit paper until you have "erased" the 80 grit texture and replaced it with a 120 grit texture. Then, only move up to 400 grit when all the 120 has been changed to 320. You do this because it is very hard to remove heavy scratches with a fine paper.
Also, all grits finer then 120 were hand sanded because they don't sell fine grit sanding disks. I broke up the work to one grit per day, just so I would'nt rush it and leave scratches behind. After 320 grit I moved on to 400, 600, 800, 1000, 1500, 2000. I could've probably stop at 1500 or 1000, but I wanted a real shiney chrome-like look. 800 and up grit I wet-sanded.
At this stage the piece should be really, really smooth but not shiney, more like a dull grey, similar to anodized aluminum. Inspect it to make sure everything is sanded and no noticable deep scratches have been left behind. Once, your happy with it go have a beer, the hard work is done!
Polishing is alot easier, you'll be using both the drill as well as the dremel along with an asortment of polishing compounds and buffing wheels. Here's a link to where I bought mine if you don't have them:
http://www.hobbytool.com/polishing.htm
Use your drill on the big areas and use your dremel for tighter areas. You should be able to get every area using various shaped buffing attatchments. I used the black compound, then brown, finally the red. Each one the aluminum will get shinier and shinier. It'll blow you away when the first compound turns the dull metal to almost a mirror like finish! The final result is going to depend on how well and complete you sanded, so put in the work if you want it to look good! You could probably do one piece in a weekend if you do nothing else.
