Dan Carr has a poster out with all a-body production numbers on it. This is a very informative poster. They are $28.00 + $6.00 for shipping. I have one and it's full of good info if you are into the numbers thing.
It list the models,engines,transmissions and how many SS elkys were built. See what it looks like at the link below.....
http://www.designscomputed.com/auto_pub/a_body_68_72.html