[elmariachi]

Check it out. Here are some pics from a shortblock I looked at buying here in Houston last fall. Showed to be a C5AE-G, casting date January 8, 1965, same date as yours. It was stamped HM138 in two places, which I would suspect meant Holman-Moody.

Very cool that they'd have the same date and no surprise that HM would have gotten the very first of the new castings. This particular engine had 4 sleeves and had then been bored to .030 over. It had definitely seen better days. Sorry for the poor focus, these were taken with my Blackberry because I didn't have my good camera with me.