I would bet this would not work. I bet these axles are designed to keep metal "grain" intact for strength, heat hardened and I bet the little baby tube you slide over it would crumple under the torque.

If your engine makes 150 ft lbs of torque, times first gear of 3, times low range of 2, times gear ratio of 4.3. That front axle could see stresses as high as 3870 ft/lbs of torque. Yeah you can halve that with 4wd, and maybe halve it again if you are driving straight and the other side gets some torque. You could even cut it down to 1/10th of that if most torque is lost in tire slip.

So say 100-1000 ft/lbs for argument's sake.