Check out Kore 3.
http://www.kore3.com/proddetail.php?prod=10277-01
You can order their brackets w. internal parking brake mechanism without purchasing rotors pads and calipers you already have. I purchased this set up for my c6 zo6 calipers/rotors and it works great. The design is really slick and looks great. IMO its the cleanest option retaining the brake internally like gm intenteded. No need for an additional caliper for the parking brake or adding one to the pinion yoke. -Andrew

(I had the opposite side brake actuator installed in this pic, thats why the lining isn't centered)