Unknow 1968 RR Fender Tag Option

[68RRBP2twotone]

My uncle also has a 1968 RR he is restoring. Yesterday I was decoding his fender tag and it has one option I can not find anywhere. As you can see above it has a 4 under the C and I can not find a reference to this option. Anyone got any idea what this option is?

 

[68RRBP2twotone]

Something else that is odd about this car I found out. My uncle bought this car from the second owner and he swore that the in dash tachometer is original. If that is the case it should have a 7 under the T. Could the 4 under the C have anything to do with it having an in dash tachometer? Just grasping at straws here.

 

[69Coronetrt]

C/4 = code 624 = HD suspension

Commonly found on STL plant 'early' RM21 383 cars.

 

[68RRBP2twotone]

Thank you very much 69Coronetet! It is a STL car and it has an October build date. You are the man! Thanks again.