Front or rear? Usually if it's a rear on a Trackick anyway, the studs are pressed into the rear axle flange. To do it right you'll need to pull the rear axle out and press the broken one out then press the new one in. On the front you should pull the hub off, press the broken one out then press the new one in. Reassemble everything when finished. If you don't have a press, Ive seen some guys do it with a BFH and some kind of block to support the hub or axle. If you aren't comfortable with any of that take it to a shop.