Thanks for the help. Unfortunately, the guy who posted the thread on the "other" site (don't get some of the the animosity toward that site that I've sensed here from time to time - not from you, Tama - I've gotten great answers to some very challenging questions there - there's just a much larger body of knowledge, when you add in all the 924/944 folks) also didn't find a tool to remove it. Sounds like he ended up going at it with vice grips.
Yes, I understand why the airbag control unit is not intended to be removed, but I'm turning my car into a track car, so it will 1) very seldom have a passenger, 2) It will have a full harness, and 3) I disabled my passenger side airbag years ago, when my oldest daughter became tall enough to ride in the front. And I've already removed the air bag module itself, so there's no danger of it going off as I work on removing the control unit.