Transplant the motor, transmission, transfercase, and axles from a Dakota or a newer Jeep into the Willys. The older Dodge truck axles would be a bit too wide, the Willys is a narrow body and frame. Maybe you can put the Willys body on a Ramcharger frame? Can be done, probably been done before. I put a 50 Dodge cab on an 80 4x4 chassis, it was a lot of work to make it fit, a Dakota chassis would have been a better match. Gene