I have a copy of Mortec web site to identify casting numbers but i would like a copy of how to decode ID pads in front of the SB Chevy.I am going to look at a motor that has a 39710010 number and according to my copy it could be a 69z28302 (no such luck)or a 69 327 or a 69-80 350 which i hope it is, how can i tell when i get there?

Try this:

http://www.nastyz28.com/spmenu.html

graemlins/beers.gif

Shocker, Just post the pad numbers, cast numbers and stamped Vin number in Tag Team and we will decode it.