My Wilwood hubs use slip on rotors. Factory e-body drum spindles.
Do you have pics or part numbers? I saw some wilwoods, but they looked like the kind of hub that uses a 2 piece rotor, and the friction surface bolts to the back side of the hub. I'd like to find hubs that use true slip on rotors so I can use any rotor with the right bolt pattern.
I don't have any disassembled photos but their instructions for the ebody kit has good exploded diagrams. My rotors are multi pattern slip on.