On my 2001 I am fortunate to have the chrome cases, as well as on Mrs. Irish's 2002 Bonneville America, however the "new" 2002 T100 we recently bought her has the clear coated, brushed aluminum cases and the clear coat is looking rather ratty. So I am interested in this thread also.
I am leaning toward getting them powder coated. There is a place in town that my friend told me about and I called the guy. He was familiar with the Bonnevilles so he knew the cases in question and he quoted me only $100 over the phone to do the work. I thought that was extremely reasonable.
I think I am going to take them off after it gets a little colder outside and bring them over there. I am going to take a look at some of his samples, but I am leaning toward a finish that looks almost like polished aluminum.
Here is a link to his web site:
http://www.coyotecoating.com/
I think they ship...