When it comes down to the 1967 hemi block being cast there were a lot of blocks cast in the 1967 manufacturing year. If you look at the casting dates.

6 14 66
6 27 66
8 16 66
8 23 66
8 28 66
10 10 66
10 31 66

There could be more dates to add from June to December in 1966. Also for the longest time the 1967 Hemi Build number were not correct and very low for know built Hemi Vehicles. Not all motors make it into Vehicles and motors were sent to Drag Race Teams, Nascar Teams and for Marine use and the General Public Dealer Counter sales.