I just finished a complete polish of my MCI9. I polished all the stainless as well as the rear view mirrors, taillight assemblies.... I learned a bunch while working on the 6 month project. First, follow the directions available at this website, as well as purchase your supplies from these folks. Very easy to work with, great products and always willing to answer questions. I used the gray then white compound as described the got a mirror finish around the bus. I used 6 3lb bars of gray and 2 3lb bars of white compound. I removed all the rub rails, bumbers and turn signal assemblies to make the job easier. I used a 9 inch grinder from Harbor Freight (x3) and 15 nine inch wool bonnets. It did a bit at a time and listened to a lot of good music (cost does not include IPOD and hearing protection).
I got a roll around chair as well as suspended the polisher from my roll around ladder. I spent $350.00 on supplies and equipment and sixty hours for the entire project over 5 or 6 months. I can see why some folks will charge $4,000 or $ 5,000 dollars for this project.
The link below can get you all you need.http://www.swmetal.com