Foundthis on th ed ck of my C0BA... 0034138. It had been star stamped over and above it is 8799. The second number I believe is a rebuilders number but what is the first number?
You're likely to find that most of the numbers stamped on a US flatty block mean absolutely nothing now; except that SOME of the late flatheads have a date code that is decipherable. Is it a Canadian block?