Your shop should be able to get gray.
We have a local body shop that does ceramic. He does not do the high polish silver anymore because it is so toxic. But he will do a gray that does not polish up like chrome. One of our local Cobra guys had his done in the gray and they look very good. I'm replacing my mufflers on my sidepipes and I'm going to get them recoated in gray. It does polish a little.
Dwight
I found a pic of Jack's sidepipes. They do polish a little.
