engine I D numbers

Need a little help. I replaced the water pump on my 72 and got the casting numbers on the block. Here they are, can anyone decode. I would be grateful for the info. The numbers are V1220CKX and 12S511046 Thanks guys!

Here's the translation:

V1220CKX is a Flint Small Block (indicated by the V) 

Engine assembly date (1220) is next December 20 (I assume 1971)

The motor is a 350 ci  engine rated at 200 HP with an TH-400 automatic transmission & Rochester 4-Barrel carb (CKX).

The "12S511046" is a VIN stamping.  This VIN indicates a 1972 Corvette made in St. Louis made probably in late January 1972.

Good luck........Anthony

Ten 15, You are the saviour of the day for me. Thanks for the info!!

Actually..........

You can thank Joel (Adams Apple).  He pointed me towards some really good books on Vette #'s.

Anthony