I just got a complete 12 bolt today and a number I found on the pass side axle tube was kdc2212. I could not find a date but is at least a 68 model rear. I did not find this code anywhere on the site so I was hoping someone has ran across this before. The gears that are in it now are 3:31 (open carrier) and by the looks, seem to be original. Just would like to know what was originally in the rear. Thanks
Caleb

KD shows to be a 2.73:1 open in the 1968 chart

http://chevelles.com/years/68/68rearcodes.html

Thanks
For the response...I had lost the post...didn't mean to put it in this section.
It was supposed to be an open 3.73 but ended up having a set of 331's but I can't complain because all I have in it is a 9" rear I bought a few years ago for 150 dollars. Glad to know what it was originally.
Caleb