i was wondering what the numbers on the top(in the back) of the block mean?? i know the numbers on the drivers side tell what the motor is but im unsure of the other ones? mine was A75? any answers?? its a 64-67 327 if that helps

 

Not sure but I do know other numbers are to identify when and where it was made.

 

A75 = cast on the 7th day of the A-th (first) month (January) of a year ending in 5.

 

'65 327 then, thanks!!