I have a '38 Packard Six 4-Dr. (Model 1600) Touring Sedan.

I would like to install an overdrive unit.

I found a R9 '40 transmission with overdrive.
Will this transmission fit/work in my '38?

I know that the '40 is a column shift, but I was hoping that maybe I could use my floor shift top cover on the '40 transmission?

If I could find just a overdrive unit (R9/R10/R11), could I install one of these on the back of my '38 transmission? I know that I would have to shorten the driveshaft. I also know that i would have to install the appropriate control cable and wiring for the solenoid.