Has the syste been stress tested by riding without a rear chain installed? 4X4 enthusiasts are known to remove their broken rear driveshafts or axles and drive out of remote locations on just the front axle. I am also suprised at not one mention of Nethercutt or Rokon industries, which have been making the "Trailbreaker" 2WD "mototractor" since the early '60's...