I Just removed the upper control arms on my 2000 Xk8, I knew the ball joints were bad from replacing the upper shock mounts. One ball joint literally fell out. The other was a PITA, frozen. I tried a hammer, heat , pickle forks with no luck. I was desperate. I finally took my ball joint separator (from Harbor Freight) and just went all in. I had used this before but backed off as it seemed the pressure was going to break it. Put the ball joint separator on and with a 3 foot breaker bar went at it. Quite a loud pop when the ball joint finally broke free. I also had literally applied Liquid Wrench, I don't know if it helped but it did not hurt.
Regarding the fulcrum bolt and getting it out. I took a rubber mallet and tapped the end till there was about 3/8 or a inch. I took a Pitman arm sized pickle fork and with a rubber mallet tapped the bolt out. At this point I had enough room of the bolt out to clamp on a vice grip (protecting the bolt with a rag) and used the pickle fork between the vice grip and the edge of the control arm to easily tap out the bolt, moving the vice grips as needed.
Next step, find a good mechanic with a press to remove and install the new ball joints.

Ball Joint separator

 

should be easy to find someone to swap out the ball joints - upper is much easier than lower. If ya lived closer, I'd have said bring it over - 20ton press sitting in my garage

 

I actually managed to shear the pivot pin on my separator. I just used a high tensile bolt in its place. They go off like a gunshot when they release! Good luck with the rest of your project. It's very satisfying when the job is complete.