Idk... This one might pass as legit... ::)
My favorite line:
"Internet searches: Made in Tonawanda, shipped to Michigan to become a "DZ". Or could be a re-stamp."
Chevy 4 bolt "DZ" block & misc - $1,600 (Canton) (https://akroncanton.craigslist.org/pts/d/canton-chevy-bolt-dz-block-misc/7597239814.html)
Not that it matters, but if the casting number is A 7 8, it is a 1978 casting. No 010 blocks until April of 1969. Also has the short stamping pad which didn't start until around 1974.
Of course, the "experts" will tell you, hey, anything could have happened.
Who in the world would stamp a short pad block. One thing about it, it could be the only one!
And everyone knows what it is.
It's a "Mystery Motor".
Now reduced "Chevy 4 bolt block, not likely a "DZ" & misc - $800 (Canton)"