Ok, just got the ball joints, axels and bearings finished on my 2000 GC- man, what a job! I had more troubles with the ball joint purchase, removal/replace than I can or want to tell here. Rest of the job took about three hours, but....

When I was dismantling the steering knuckles, I had to pull the ABS wheel speed sensors. Passenger side was stubborn and wouldn't pull loose and I broke the little plastic stud off in the knuckle. I put it back together with new axels and hubs and was pretty sure I got the sensor in the right position, but now my ABS light is on. How critical is the sensor placement? Also, I painted the knuckles(since they were out) with rusty metal primer, could this be a problem?

You probably destroyed the sensors. They are a magnetic switch that reads the notches in the axle stub just outside the CV joint seal behind the hub bearing. A DRB scan tool that most good shops have can read the system and tell you which ones aren't functioning.

Don't see how I could have destroyed them outside of the little pastic stud, I pulled,wiggled them out with my fingers.
Anyway, I'll replace them both.
Merde- always something......