That string of numbers was the VIN stamped on the rear of the block behind the intake, useless for block ID. Like 65ShelbyClone says, get the numbers from above the starter location, if it's a small block. Big block (FE's) are on the rigth side toward the front. They'll be something like this : C5AE-6015-A There'll be another set like this: 5B15 (number/letter/number(s) which is the date code. First number is the year of the decade, letter is the month, starts with A for January thru M for December they skipped the letter "I", the last number or numbers is the day of the month.