1969 Chevy C20 Engine Code Help

[DeadMansOhms]

So I have looked allover the internet trying to decode these engine codes and i'm just looking for a second opinion and had a question about one thing.

So the code on the back drivers side is 3970010
The codes on the front passenger side is (I think)
Left- FA34924 (the 9 looks to be restamped to a 2 or the other way around)
Right - _213TTP (first number or letter is blank.

From what i have found it is a 350 from a bus possibly. just looking for second opinion and was wondering why the 9 or 2 would be restamped.

Thanks for any help and all is appreciated.

[jocko]

concur, 70 350 from a C50 or C5500 (bus)