manual to auto swap what will work?

65 was the final year, but sometimes weird things happen. The only reason I say this is because iv'e come across a 66 dart that was cable shifted. But I think it was a late 65 made up of left over parts. Considering when the motor was pulled it had casting #'s for Dec 64. Originally owned by his grandparents. Same kinda thing happened with a ferd I had. 77 car with 71 pistons, from the factory.