Also.....in addition to being pretty thin walled the axle tubes are just pressed into the center housing. This can work both ways; you can narrow it 2-1/2" (approx) by popping out the left side longer axle tube, cutting out enough so you can use a right side axle or you can use it as-is and do some spot welds between the axle tubes and the center housing.
The TracLok (posi)feature, can be easily checked for excessive wear with the diff still in the vehicle......simply select one that has a minimum of play when you push-pull on the hub. Even with 100K on the vehicle there is very little obvious wear on the internals and with the volume of 3.73 Posi diffs available for a whole lot less than buying a gear set and installation kit, it makes for a viable option.
Dave
