2829317 first appeared as a production trans for the compact truck (A100/108) in 1967.
It also appears as a production unit under the same p/n for 1968

The date code means one thing and only one thing - when the unit was made, not what model year it fits.

Looking at 2540 date code that is July 11, 1968. Tight but it could have been installed in a 1968 vehicle.

Could be a service unit for a warranty replacement back then.