Hello all, I was wondering if anyone could tell me where to find out what the RPO codes on the door means. Thanks in advance

These are the codes that are used for replacement
part info & service repair. Every option has a related code to identify it. A good example would be
if you had your car stolden, you tell your insurance
co you had a c/d player, the build info says it was built with a UM6 option, a AM/FM-CASS.
Your dealer can run a printout for you, that will list all the codes & what they are.
If you need something specific, like gear ratio, ect
I can help.