I have thought of the slotted drilled rotor also, but my concept was to have the rotor ground flat, then a slot end milled on both sides of the rotor only as deep as required were the internal dimension was not less than that of the minimum rotor thickness specification. The slots would not be all the way through the rotor...
Hey ProTeal, can you supply a photo of your plated rotors and provide the name of the plating house that did the work?
Scott