7N222201MQ L78 Block on Fleabay

[HarrisFD]

https://www.ebay.com/itm/MQ-1967-Camaro-Big-Block-Chevy-396-375hp-4-Bolt-Main-Block-3902406-406-D-14-7-/373522801244?_trksid=p2349624.m46890.l49286

Weird "MR" stamp after MQ

[CantRepeat]

That is weird. I'm eager to learn if it's an actual factory mistake or just a horrible restamp.

[70L34]

I would guess it is legit. The MQ stamp looks good. MR was L78 with smog, which would have been odd to see coming from Norwood production.