This weekend we installed the rear disk brakes (from a 2002 Chevy blazer) on the 12 bolt rear end. We had already pulled the axles and installed 2 inch studs. Picture 1 shows a spacer we bought from BRP Hotrods. While the swap appears to work without the spacer, the spacer centers the caliper directly over the rotor. Next we bolted the caliper brackets to the rear end. Then we had to slightly enlarge the center of the disk brake rotor so that it would fit over the axle shoulder. Eric used a drill with a small grinding stone and quickly opened up the center so it would fit (Picture 2). Picture 3 shows the completed passenger side. Next we will install the driveshaft and rear wheels.