Last year I played around with powder coating with a cheap kit. Here's some pics of my brake calipers.

 

Not bad. Have you done anything else? I've been thinking of getting one of these kits. As a matter of fact there's an article in this months PHR for one that looks good.

 

My aluminum TB plate. You can do anything that will withstand 400 degrees for twenty minutes. And it adheres to the material better. You just can't use a oven you eat in and it has to be electric, but it should come with directions.