I asked whether the pups were from SD and this is the answer I got:
"No. Jim DeCola designed them.
*Features large diameter Alnico V pole pieces for an expanded magnetic field. These magnets, combined with the coil windings and wiring, create an extended frequency response, fat and punchy tone , higher output plus low noise operation due to the switching scheme.
The vintage style three way switch scheme permits the following selections (all in humbucking configuration):
Neck & middle
Neck, middle, & bridge
Bridge & middle"
So just like the original they still work in pairs or more which means that they are true single coils after all. A Gibson with single coils, a rare breed.