How do you tell what year the cases are on the older Iron head motors? I have one set that has the numbers #24558 73 and it was sold to me as a 1973. I have another set that is numbered # 24558 75 that was sold to me as a 1980. These numbers are in the inside of the cam cover side of the case as well as on the inside of the transmission side of the cases. But, are these numbers the year of the cases, I hate to assume anything.
Maybe the numbers on the case below the pushrod area tell the story?