Patrick's has a kit for mating a Saginaw to the torque tube. See page 14 of the catalog.

When I was a youth in the early fifties, the cool transmission for a stovebolt was the 1937 Packard. HRM gave instructions for the conversion. When Chevrolet came out with the open diveline in 1955 I converted my '53 to open, with a mid-ratio three-speed.

Hoyt