1969 Chevelle where to find build sheet?

[Bad69Chevelle]

I am in the process of buying a 69 Chevelle. The seller said that it was a matching numbers motor but the numbers on the front of the block were machined off when they bored out the motor from a 396 to a 402. Are there any other areas on the motor they put the numbers? It is a Fremont CA built Chevelle with the 72 paint codes wich by itself means an SS but i would like to still verify the the numbers match. I would also like to know the most common areas they placed the build sheets in the Fremont built cars.
Thanks Larry