The rear trailing arm bushings require a special tool. You can make your own with the information at:
http://www-ese.fnal.gov/People/wilcer/volvo_trailing_arm_bushing_tool.htm

The tool is not difficult to fabricate and it works well. Make sure to go to the added effort of getting the hardened bolt and nut.

The other bushings can be done with a very large vise but are most easily handled by sending the components to a full service auto supply store and allowing their machine shop to swap them out.

The rear trailing arm bushings seem to be the ones that take the most abuse and many times do need replaced. However, I am of the opinion that many times the other bushings are just fine and are replaced needlessly. I base this on my own experience. At 137K I would be willing to bet you only need rear trailing arm bushings.

Randy