I ordered an entire set of mirrors from streetinspiredkustoms.com. I actually ordered them though ebay. My truck came with the giant extendable towing mirrors. I ordered the regular mirrors and put them on my truck.

 

Your standard mirrors have a black textured cap that is held on with 4 tangs and double sided tape. They pop off fairly easily, just be careful. Painted caps come with the double sided tape ready to install.

 

Cool, seems like waste on Gm's aprt, why not have painted ones or chrome on them all, or a solid painted mirror...oh well!!!