Did you look at the Tranzilla? I really want someone to do this and be the guinea pig (but it ain't gonna be me!)
Rockland Standard Gear 6-Speed TRANZILLA 4×4 Transmission
https://www.motorator.com/blog/general-automotive/rsg-tranzilla-tremec-6-speed-conversion/
Make your 4×4 drive like a sports car. Rockland Standard Gear (RSG) has unlocked the true performance potential of 4×4 vehicles with its new 4×4 TRANZILLA Tremec T56 Magnum 6-speed manual gearbox. Designed to replace traditional balky-shifting, wide-ratio truck transmissions with the smooth shifting, closer-ratio transmission, the RSG 4×4 TRANZILLA transforms the 4×4 driving experience. You have the perfect gear ratio for any situation right at your fingertips. Effortless up- and downshifts ensure that you have the right gear for climbing that hill or pulling out to pass. Plus, the two overdrive gears provide improved fuel economy and reduced powertrain vibration for freeway driving.
Available for Chevy, GMC, Ford, Dodge and Jeep vehicles the 4×4 TRANZILLA is available in three torque ratings – 500, 700 and 850 ft.lbs. The higher rating will handle supercharged, big-block and even most diesel applications.
RSG’s 4×4 TRANZILLA will work with any 27 or 32 spline input shaft New Process, New Venture, Atlas or Dana 300 transfer case. The transfer case can be “clocked” (rotated) incrementally in either direction. Overall length from the front of the transmission mounting plate is 39” with a RSG 231HD slip yoke eliminator as shown in the photo. Shifter location is 20” from the rear face of the engine block.
