I'm rebuilding my front-end and I can't get the damn lower ball joint stud out of the lower control arm (driver's side). I got it out fine on the passenger's side, but this thing just won't budge. I've gone as far as putting the control arm in a vise and hitting the stud with a 10-lb. sledge hammer. Now all I have is a mushroom'd stud. What the hell is up? What else can I do?