Engine identification
 

I was wondering how I can identify whether or not my engine is original to my truck.
I have a 1977 chevy c10 that I recently got from my parents.
My parents have had it since 1989. Any information about it before then is somewhat sketchy.

There are casting numbers on the block that will tell you what era the motor is from. Here is a link to a web site that might help you...
http://www.nastyz28.com/sbchevy/sblock.php

Thanks!
I will check that out.

Found the vin code format.
matching numbers.
Only thing i am unable to figure out is why the first character is a 0