How to find paint codes for OEM wheels

[jbreeds09]

I have GM OEM accessory wheels, 22 inch 7 spoke CK163's, and I am looking for the paint codes to have some touch up work done (Atlanta's roads are horrendous).

 

Does anyone know of a method to find out color codes for painted OEM wheels?

[Thomcat]

I've had no luck over the years trying to get this info from dealers, or at least to provide the name of the manufacturer of the wheels to contact them directly.