[rotorwrench]

The Ford passenger and light commercial vehicles were all closed torque tube drive with a single transverse spring on the rear axle housing. Any of the rear axles from the model A up through 1941 will fit the width requirements and the post model B stuff is stronger than the earlier ones. This was the basis for the traditional AV8 converted hot rods. When you use an open drive with removable drive shaft, the whole suspension has to be changed to work with it. Take the torque tube out and some form of triangulate radius rods with a third torque arm has to be put in there to hold things square unless dual leaf springs are used but that would be difficult on a model A frame. It's all been done before but it's more work than shortening a torque tube and drive shaft.

I assume you looked at Mike Bishop and Vern Tardell's book on the AV8 but maybe not? This stuff is kind of a HAMB thing but folks ask on the early V8 side about stuff like this to some degree.