D60-2
In the late 60s/early 70s J-Truck configuration it is 35 spline, semi floating, 1.5" axle shafts and 66" WMS offset 6" or so to the passenger side. 5x5.5" bolt pattern
There are two very important reasons that they are useful:
1. If you shorten the long side to take a short side shaft, it centers the pumpkin and Creates a ~60" WMS
2. The bearing retainer bolt pattern is the exact same pattern as a Chevy spindle. That means that you can convert to disk brakes using chevy bolt-on front caliper stands and/or convert to full floating very easily.
I overcame the 2.5" axle tube issue by inserting a piece of appropriately sized heavy wall tubing into the ID of the axle tubes. The same thing can be done to align the two halves of the long side when you cut them off.
They also use a 1310 U-Bolt Yoke. . .
I ran mine on my CJ for years, but one of the reasons it is in mothballs in favor of the XJ now is that I feel like you need at least 38" tires for the D60 center section. That is going to require a lot of time with cutting tools and my wallet.