alright, this is on a 96 impala if that makes any difference but i think its the same. i am putting drop spindles on my car and am i've started putting the new ones on but i am not able to torque down the castle head nut onto the ball joint studs on the upper and lower control arms because the stud freely rotates. i've tried jacking the control arm up to put weight on the suspension, and i've tried leaving it to hang but i cant find a way to do it. is there a trick to it?

 

It could be that the ball joint is worn out. It should not spin very freely. You may also need to clean the tapered sections of the stud and the hole in the knuckle.