I googled the 590822 and it is for a 37 to 39 master deluxe. I wonder if it will fit the truck. I put the shifter from the other transmission on the truck
and it has the same problem so I'm thinking it's in the transmission. One of the other threads discusses how to detach the torque tube.
Looks like I'm going to have to learn more about torque tubes than I ever thought I'd need to know.