Re: 9inch diff into XD
No, they are different rotors. The XD rotors fit over the outside of the axle flange (over the wheel studs) and is secured by one countersunk Phillips screw. The rotors on XB/C 9" rear ends fit up behind the axle flange, and are retained by the wheel studs being pressed through the rotor then the flange. Consequently, the back of the flange has to be machined flat for disc brake applications - can't just use a drum brake 9" axle without modifying.
Sorry for the bad news.
BA GT #0909 - Manual, Citric Acid, Stripes, Sunroof, Premium sound, FPV Steering wheel and Mats.