The peening process was called "swaging" and it was done with a special hollow punch for an air hammer. A new stud will probably have a slightly wider spline that can be pressed into the hub or axle flange and cut new splines as it's installed. DO NOT try to pull a new stud in with a lug nut- - - -you'll stretch the thread and weaken the stud. Either use a hydraulic press, a ball joint press, or an air hammer on the back side of the stud.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!