[John Rogers]

The guys giving you advice must really hate Miatas since beating on the damaged stud is probably the worst thing you should do. I would suggest doing this as shop would do it and first buy a new stud, the same as the original ones. Next would be to pull the hub off being careful to not damage the wheel bearings and then cover that area with clean cloths to keep dirt out. Next use a press and remove the damaged stud being careful not to warp the hub in any way. Next press in a new stud being careful not to warp anything and make sure it is seated fully. Then put the hub, brakes, etc all back together CAREFULLY.

Note, if the nut is jammed on the existing stud and you try a moderate amount of force, cut the stud off and that will prevent possibly ripping the hole the stud is pressed into and then ruining the hub!

If you do not have a press, now is the time to get one and I have had a Harbor Freight, bright orange monster that goes to 25 tons pressure (uses a jack) since 1998 or so and it gets used several times a year or more!