The original studs in the knuckle can be reused if undamaged. We used a punch to hammer the studs out. If you don't have a punch, use a nut on the stud to avoid damaging threads. We installed the studs in the new knuckles by hammering them in using a solid brass bar. Make sure each stud is solidly seated in its hole. This will be slightly easier if you remember to install the studs before pressing in the ball joints.