FYI, I am changing from wire to disc wheels. Have not found where the hub needs to be changed as well; just the studs.
That's right; the hubs only had different part numbers because they came with the studs loaded in them. Only the studs are actually different.
Changing the rear studs is lots of fun, though. The studs are threaded in from the face, then peened over in back like a big rivet. On the later cars (with front disc brakes), the hubs tend to "become one" with the shaft; even having the special factory puller is no guarantee of success in removing the hubs without ruining them.
My suggestion is to remove the hubs and shafts as an assembly (locktabs & 6 bolts behind the axle flange) to get access to the back of the studs. Then you can see what you're doing as you grind away as much as you can without damaging the hub; then unscrew the stud as far as it will go. Turn it back in and grind some more. Repeat as necessary.
The good news is you can leave the brakes in position and don't have to open the hydraulic system. The bad news is that you should recheck the axle end float (with a dial indicator) once you've got it back together. This would also be a good time to change the inner oil seals.