Need help!--W/S/W linkage parts
 

The W/S/W linkage on my "new" '82 300SD was disconected from the motor when I got it. It appears that the joints had become stiff, and the excess effort required to move the blades caused the link to pop off the ball stud. I disassembled the linkage, cleaned and lubricated everything. Now it moves with ease. However, the ball stud is so loose in the socket on the link that i am afraid it will just pop off again.
Does anyone know of a supplier for those ball studs and sockets that are used in W/S/W linkages?
As an alternative, I was considering this repair; drill and tap a hole in the top, center of the ball stud. Grind the top of the socket off. Place the socket on the ball stud, and use a washer secured by a shoulder screw to retain it. Is the material the ball stud is made of a special heat treated steel? Will it be possible to drill and tap into it?
Any other possible repair methods?
Thanks for the help!

Hard metal in that ball socket, however I have drilled & tapped several just like you suggested. I allowed the screw to bottom out & still have some clearance between the large washer I used & the plastic on the linkage. USE red loctite on the screw.