Dude,
I had a 1968 M715. If you do a spring over in the front, and a shackle reversal in the rear, you can easily fit 44's, I put 38" boggers on mine without any modifications. If the rest of the running gear is stock behind the motor, you have a t-98 4 speed, a Dana 200, which is my understanding similar to a Dana 300, but it had bushings instead of bearings, which makes it stronger, but it will heat up if you drive it over 60 mph and boil the oil out. I filled my t-case with synthetic and I didn't have any problems. The axles will be a Dana 60 in the front, and a Dana 70 in the rear with 5.38:1 gears. Mine had a metal top that was basically sheet metal formed over the soft top framework. When I removed the sheet metal, I could fold down my windshield. I sold it years ago, and kind of regret it ever since.
