Are you going for a contrast stitching colour on the interior? If so you can match the callipers to pick up that interior accent i.e. silver stitch - silver callipers, red stitch - red callipers. You might want to consider a grey opaco finish on your wheels. That's the flat grey metallic (non laquered) finish that Ferrari gave the 430 Scuderia wheels. It looks great against a black exterior IMHO.