Going back to the date codes for a moment, there are 'cast dates' on the calipers, and also stamped dates: on my two calipers from my 09C (1969) Z28, on one caliper was a cast code of 143 (23May), with stamped date of 168 (17June). On the other, was a cast date of 188 (7July), and a stamped date of 227 (15August). All of these dates seem reasonable to me for calipers. Am I interpreting the cast and stamped dates correctly? The castings are done, then some time later, (3 to 5 weeks later in my caes), the parts are machined, the calipers built/assembled, and the assembly dates stamped in. Note: My '227 stamped date actually seemed to be 00227, but I interpreted it the same way?