I saw this on SVTP (or somewhere) so thought I'd give it a try. I always hated the look of the stock and GT500 mufflers hanging below the rear bumper cover so I painted them (GT500's). Looks about 1000 times better black than silver. They fade into the under carriage nicely and you don't notice them at all anymore. 2 coats of Rustoleum High Temp (2000 degree) flat black.

Before, during, and after pics...