The 0D10 on the one head resembles the casting date,which would be April 10,1970. The # on the other head "130", is not a complete date code if that's what it is. The head casting #'s are only the C4AE-6090-F, the other #'s refer to casting dates etc. The casting date should also be on the block. A 1970 date would indicate a service part. An easy indicater of a service block is the vertical ribbing on the side,which weren't on the early ones. Just trying to get the info straight.
