The ball should not "slip out" of the socket. If it does, it's worn and failed. It should only come out when you dissassemble the valve, pull the guts out, and this will let the sleeve move. Once you get the sleeve to move outboard, the ball stud should come out. THe only difference between the one that unscrews from the center link and the one that does not, is that it is much more difficult to get the sleeve to move, and to get the ball spacer plate on the far side out once the stud is removed. Soak the sleeve in PB Blaster or simular product. Work the sleeve loose. It will fight you every fraction of an inch. Especially if it's rusted in there. Resist the urge to pry the ball stud from the socket. It will only come out one way in one position by hand. If you have a complete rebuild kit, you may be forced to eventually pry the ball stud out and remove the sleeve forcefully. Try not to, but sometimes...make sure you get all the rust out and the new sleeve slides in snug. Some of the new sleeves are not as sturdy as the original and will ot take a lot of manipulation. Although once it's all together it should hold everything nice and tight. Check your shop manual and follow the adjustment proceedure. Make sure you grease everything up good when your ready for the final assembly.
