Rear Disc Brakes

What was your cost of the complete system, if you don't mind sharing.
Did you use an A-body rearend with aftermarket axles and bearings or a
B-body LBP rearend.

I'd have to go back in my files to find out the cost. It ought to be pretty close to the current Rock Auto prices I'd guess. As Dano posted below, they are in fact the 94-04 Mustang calipers and rotors. I sourced the pads and hardware locally for less than $40. I got some core calipers on the cheap and used them as my trade-in at Rock. After I received the rotors I had my machine shop guy turn them 40 thou to fit the LBP axle hubs. Dodgedifferent2 opted to turn his axle hubs but as he said it can be done either way. The housing is a stock A Body rear end and I used shortened/re-splined C Body axles I had. This set-up uses the stock taper bearings - which I had installed new. I would think his caliper adapters would also work on any 8.75 that uses LBP axles. I might even do the conversion on my 67 Charger, as it was pretty easy to do.

Looks like 94-04 Mustang V6/GT calipers and rotors. The Mustang calipers have an integrated parking brake.

Lack of parking brake is a no go for me.

You are correct in the Mustang rotors/calipers. Unless I run antique tags in VA (no inspection)I need a parking brake. Once I get the rear end installed, then I'll see about connecting the wagon's intermediate cable to the Mustang calipers.