Back in the 50's before there was a "Hone-O-Drive" driveshaft inline overdrive we made a case that held a Borgwarner OD unit and mounted it where the center hanger for the 3/4 ton changes from a torque tube to an open driveshaft. Chevy 3/4T used this torque tube/open drive set up for several years. It kept the same closed drive tranny but turned the 3/4 tons 4.56 gears to a 3.20 final when in OD. The first case didn't have the input shaft to the OD straddle mounted in spread apart bearings and gave trouble but after this was corrected it pulled our Hudson circle track car thousands of trouble free miles without the engine screaming like a banshee.
