If you do a SAS some of the things to think about are there are sensoer on the front axle for the ABS and the TOD. In order to retain those you would have to find a way to transfer those sensors to the donar axle. I plan on doing aweay with both those systems ( I don't like the ABS on the trail and don't really need the TOD). I will go to a manual transfer case (low gear options not available for the TOD T- case and possibly twin stickable). The most frequently used axles are the late model waggoneer or Toy axles. The rest I am still researching.