If the rotors fit on the special KKX or DOZA-B spindles then the rotors are the special ones too regardless of if assemblyline or aftermarket. The most important thing is to have something that fits in this world of even finding a aftermarket will be difficult . I would repair/restore the ones on the car now if need be. I have a pair of aftermarket Shelby rotors on my shelves for save keeping in case one of my cars needs them. I am sure there are others like myself but it may be difficult and expensive to try and pry them loose unless they have sold the car etc. The point is for the uninformed is that ether type of special rotors are hard to find and you shouldn't pass up a aftermarket one in the hopes of finding a NOS original. You are looking at lottery ticket odds finding NOS special rotors IMO.Even finding used original ones to rebuild are likely only smaller less lottery win odds. Original are not marked with a Ford trademark or engineering number and the subtle nuances differences between the aftermarket and assemblyline are small. Once wheels are mounted even the subtle differences disappear. If every other thing on the car is original belts,battery,tires etc. then maybe it may make a difference other wise it will not effect the big picture much IMO.