Ok is it possible to find out what my RPO codes are without the tag in the car? Because mine had to have been removed because I've checked the console and looked all over the rear hatch lid and every other nook and cranny of the car and came up with nothing. I need the code ASAP because I'm trying to restore it to stock colors so I can sell it and buy a 2nd Gen. It's a 1992 z/28 if that helps any.

 

Some times there is a build sheet in the car. It could be in one of the seats stuffed in the underside or even under the carpet.
Dealers have always helped me but I was a good customer of the parts department through my shop but they can tell you the paint code by the last 8-10 digits of the vin. They may just tell you its too old but I have gotten stuff like the rear gear ration on older.
If the car was repainted a different color pull up the carpet or a door panel and see what color it used to be. Paint stores will have info on the color code that was used on what model car in that year

 

mine was a sticker on the lid of the compartment where the spare tire is usually kept...