1973 340 short block

Roy,
Actually the serial number and/or partial vin is located just above the oil pan rail on the passenger side of the motor. What you posted up near the head is the assembly stamping and the casting numbers are the larger numbers on the passenger side there. You may need a good wire brush or wheel to see the Vin pad/stamping. It looks like the photo I attached.

4A0521BF-7562-480C-9534-D9A54C99316B.jpeg