'94 F150 2WD. I was installing a new lower right ball joint, and while tightening the castle nut, I finally realized the entire ball joint shaft was turning. Now I can't back it off so as to get the cotter pin in. Should I just forget about trying to put pin in ? Double nut it ?

 

No put a jack under it and use it to push up on the knuckle

 

yep, that worked. tks !