I hotlinked those both from their respective threads here.
Yours was one of the threads I found last night when I was looking to fill in the blanks BEFORE I made my post;
HERE is your original thread.
In the case of the FB block, it was a 1968 block produced as a SR engine during the 1967 calender year - so there's little to be confused about (meaning it was a 1968 block cast during the 1968 model year, as a service replacement engine), and now that I have received some feedback I am confident this guy is just upselling (intentionally or otherwise) his block
I did find a very similar (albeit legitimate RA block) here - cast a month after the FB block;
LINK
