Don't do anything with the ball joints. You can move the whole cross member forward. I moved mine 1.25" forward. Yes it is a lot of hole drilling and then filling the old holes with plugs and welding them up, but it is so worth it. Check out my build page:
http://www.duallyscene.com/threads/16283/31 It should give you a good start. Everyone I know who has messed with the ball joints has told me they regretted it. Another plus is that if you move the cross member then you do not have to tub the fire wall. Just some thoughts to consider...