I dont know whan the ad was printed. It was swiped off the internet somewhere (probably an Ebay auction).
All the SD"s I have had were for the 750K models. I have never seen a rear SD wheel that would use the stock rear (F) disc braking system. The rear disc mounting bolt measurements on the K rear wheels (diameter, bolt pattern,etc) were identical to the K's front disc (6 bolt), but used an aftermarket disc and caliper. The Hurst disc was mounted directly to the wheel and the Grimeca disc had an adaptor of sorts to get it mounted to the wheel.