I just leave the exhaust tips dirty, so it looks like I drive it a lot. Which I do. They look flat black.

I'll hit 100K miles probably next week.
__________________
Richard
2017 2SS SIM convertible, A8, NPP, MRC, 56R wheels, GM CAI, Diode Dynamics Side Markers, Mamo Throttle Body
Delivered: 08/15/2016
#TeamBeckyD
