Odd 67 transmission
 

Any thoughts on this one?

http://www.ebay.com/itm/Rebuilt-1967...wAAOSwmfhX6VkE

Has the 68 maincase cast #, but a 67 production year assembly date. Case has a June casting date which matches up with the early July assembly date stamp. Shifter connections are the later style so that must have been changed. Or it is really a 69 trans that has for some reason been stamped with a 67 model year assembly code.

Anyone ever seen an original 660 case from the factory in an extremely late built 67 Chevelle or Camaro?

Thanks!