The problem with (some of) these internet threads and not here specifically is the perpetuation of a lot of inaccurate information from the non GM issue I.D. guides.
https://nastyz28.com/chevy-engine-code-stampings.php http://www.chevyasylum.com/tech/decode.html http://www.1968ss.com/sbcsuffix.asp more links to help.
I was talking to a guy recently & I told that I had a 50 Merc wit a Chevy in it and he said a Corvette engine in it & I said No 327/300 from 63 Just my 3.5 cents Live Learn & Die a Fool
Well now it’s worth more. You can take it out and sell it and not be lying about it coming out of a corvette.