I've done it with the spring installed, but I recommend taking the springs out to relieve the tension that is placed on that bushing. It is a bear to get everything back together with the spring installed.
If you are going to go so far as to take your spring down, be sure to replace everything you can. Especially the subframe bushings that the track rod mount is retained in. The removal of #20 is very straight forward once you are under there. Be sure to carefully measure your track rod length as I have found that the length of the mount threads can vary. I would recommend measuring from the front of the track rod to the front of the mount.