Dodgey wrote:Easy with the right tools, and no, you don't need to remove the ARB. Here is the low down:
To change front wishbone ball joints you need to:
1) Jack up the car and then support the chassis with an axle stand (I use 2 for safety) - you have to do this as the jacking point is actually a bracket you need to undo later.
2) Remove the wheel!
3) Undo the long bolt holding the wishbone to the chassis at the front end and remove it - you will likely need a breaker-bar for this (long socket wrench for leverage). Undo the two bolts holding the D bracket to the chassis that holds the other end of the wishbone to the chassis - again, you will need a breaker bar. I certainly did.
4) With a 27mm or 1 inch spanner, remove the castle nut on top of the wishbone ball joint - you have to remove a split pin 1st.
5) Spray the now exposed bolt where it goes into the brake assembly with Plus Gas or similar (releasing agent) and leave for half an hour or so.
6) Release the ball joint from the brake assembly by either hitting it hard with a lump hammer so the shock breaks it free (very lucky), or beat it with a ball joint separator. The Plus Gas is key here. Without it you may be bashing it for half an hour. With it, maybe 3 or 4 hits.
7) Now the whole lot (wishbone) will fall off.

Press out the old joint and press in the new one. This can be done with a vice apparently. I have a hydraulic press. A friendly garage should do this for you if you slip them a tenner. Takes a couple of minutes.
The key things you need are a breaker bar, plus gas, a 1" spanner (or 27-28mm) , and preferably, a press. Without the breaker bar and plus gas it's a nightmare of a job. With them, it's a doddle.