wheel stud sizes? my new studs are too big diameter for the hub holes…?

I had my front hubs apart anyway and decided to change the studs
on the drivers side and do away with the lefties. A long time ago I had bought new studs supposedly for this car , I found them and removed the old studs from the hub, when I attempted to install the new studs, they are too big. ... I have a 65 Polara 2dr. so I measured the hub holes and the old studs and they are alot smaller than new studs. the old studs and the holes are about 0.605" the new studs are 0.625"
I'm talking about the diameter of the shoulder (seat) area of the stud that presses into the hub.

does anyone know where I can get the correct studs ? or should I just drill out the hub...I'd rather not open up the holes.