Sweet 67 S!
4 speed?
I must say, I don't have a dog in this fight, but when I first did KH brakes I brought the hub/rotor to a mechanic friend to separate as I had no clue at the time.
He tried to press apart, using an actual press, and they wouldn't come out.
He ended up cutting the studs off flush, and drilling through them in the back side, iirc.
I don't recall much else, as a complete novice to drums and hubs and rotors held together this way, I still thought it strange.
I have another set I plan on rebuilding, the 'original' set off my car, which was fairly intact and unmolested when I got it.
I'll be taking a closer look at those, for my own edification at the least.
My 64 Fury, drums on all 4, were definitely all swedged.