is there any sure way of telling that a 69 z28/rs came from the factory with the rs option he says he has the protecto plate and that is a LA. car so no x code
VIN# 124379L516132
ENGINE BLOCK V1219DZ 19L516132
thanks

The norwood x code didnt have to do with RS anyway but on LA cars, no trim tag or VIN numbers to make it RS.
if you type in RS in the Search button you will get all the threads with the same question and all the answers. So many things to look for, not just one is the perfect answer.

thanks Jim

One of the first things I look at is the tail lamp harness. If it is an original RS harness and is unspliced you are on the right track. Make sure the tail lamp housings only have two holes for the sockets. There should not be a hole in the middle.

I look for the headlight washers in the grille and the solenoid on the washer pump (if the hood is up). I must admit I had to "rescue" my washers from the trash when I found out about them.

Jeff

Look for the headlight door stops on the rad support. All original cars will have them.

... assuming the front clip / core support has not been changed ...