Yanked the 350 outta my '78 C20 for a rebuild. Don't think it is the original engine. Tried to research the stamped block numbers, but can't match them to anything. Plus, there is a double stamp on one of the numbers. Damn! Here's a pic of the stamping. Can anyone decipher this for me? Thanks in advance.
http://imgur.com/a/dOr6y