When removing the pinch bolt on the ball joint collar the trick is loosen the 17mm bolt on the back. Spray everything liberally with PC, WD etc. Turn the wheel so the rear of the steering knuckle is exposed. When the angle is right put a big punch on the end of pinch bolt and smack it hard and decisively and it will pop out.

I spent three hours messing around trying to get the first one out and after I figured I did the other in three minutes.

 

Only use WD40 if it's all you have. WD40 isn't a penetrating oil. You'd have better results with PB Blaster or Liquid Wrench. They get in there and break down the rust.

Also a pry bar between the ear the bolt goes through and the control arm to pry a little sometimes removes the pressure and the bolt slides out pretty easy.

 

Has anyone found a source to purchase this pinch bolt ?
I changed my control arm assembly but I damaged the new pinch bolt.
My local Volvo dealer said only the frame bolts are available.
Somehow that doesn't seem right.
1999 C70 cabriolet