I have a disk brake conversion on a 14 bolt axle in the back of the truck. I first tried a driveline brake, which didn't work. Then I tried a couple versions of Eldorado mechanical brakes, which didn't work at all. Recently Wilwood introduced an electronic brake kit that I installed on the truck. It works perfectly, even for a 6,500 lb truck.
There are cheaper ways of doing the same thing using Tesla brakes and aftermarket controllers. I chose the Wilwood kit because it was easy and provided most of what I needed for a clean installation.
The kit comes with the brake calipers, controller, switch, and wiring harness (all sold separately). As it turns out, the wiring harness fits a long box squarebody just about right. I mounted the switch in a place my dog would not find in an off road bump. It is behind the fuel tank selector switch in the foreground (I'm not a photographer).
The controller is mounted near the parking brake pedal (left) and the wires to the rear calipers are shown going into a mil-spec bulkhead fitting.
I wanted the wiring harness to be as good as possible, so I sheathed the wires in DR-25 and used shrink boots and epoxy to seal the entire harness.
The hard part here is building the brackets to hold the calipers. First, they must be the correct distance from the axle center line. Second, they must be located in the right position with respect to the face of the rotor. As it turns out, a 3/8" spacer and a 1/2" plate fit exactly.
And, a shot from under the truck.
I might yet rotate them up more to get them out of the way of trail debris.
I could not be happier with the performance as a park brake. It also does a good job as an emergency brake. I've not tested at high speed, which might cause some brake fade, but at 40 mph it stops the truck just fine.