There more opinions on this subject than there are people on Moparts I have heard of a few that were put on into 70. There are a few guys on here that know more than I do for sure. My Superbird was assembled on Nov 30 and it is a cast iron piece. I think Chrysler may have slipping in a few just to help out the stock and super stock guys. By the way, I assume you are the Don Little of Stocker Fame? If so, welcome to the board. I figured you know more about these cars than most of us will ever will.