Thanks for the reply- I was totally thrown off by the in the sequence code, and the hand stamping of the last two numbers. So you agree that the 9xxxx is a legitimate sequence number and that it was a Flint plant reference? I only saw the Chevy bulletin info that refers to the original sequence of 20000 to 49999. And that would make the "A" a fitted block assembly which this engine appears to be? Learn something new everyday!