I would say unless the pieces are in really decent shape, I would replace the whole piece instead of rebuilding. The upper control arm will also more than likely need a shaft kit to go along with the new ball joint. Sometimes the threads where the bushings screw into are bad and you end up replacing the upper arm anyway. As far as the lower arm, as long as it isn't too rusty or beat up a new ball joint and cam bolt bushing can be installed. The idler arm bushings will have to be pressed out and in. Tie rod ends, just replace. If you're going to rebuild, make sure your parts are good enough to be rebuilt. If you have any doubt, REPLACE! Hope I've helped a little. Good luck!