Got the wheel hubs ground down in record time and I think they turned out well.
For those that have these styles of wheel hubs and want to do the Tacoma brake swap. I used a cutting disc, which I am really impressed with this brand/style, the Dewalt XP:
I did all the cutting with this one disc and this is all the material it took off the disc:
So I found that an initial cut just outside where the wheel stud "shoulder" is was just enough material to get the brake rotors to clear and not a hair more. This is looking at the backside of the wheel hub.
So to add to my stupidity. I blindly bought wheel studs a year ago with my tacoma brake rotor mounts from FROR, it's what they say to buy when doing this swap... They're 1/2-20 threads and longer than stock. Factory toyota (as my internet research tells me) is that they're M12-1.5 thread pitch. Well, my problems start with them being the wrong thread pitch for my lug nuts. Second, they're too long even if I bought new lug nuts (which is not even a consideration, since I would then have two different style lug nuts on the same truck, plus they're wheel specific...) Figure that the lug nut would be about an 1/8" off the rotor when the wheel is mounted. The lug nut would bottom out before it was tight.
Back side of wheel with lug nut through it for visual.
Thread compared to the toyota rear axle.
So I'm not sure why FROR sells studs that don't match the trucks that their taco brakes mounts are going on, Maybe I'm missing something...
I emailed them.