You're right about taking your time Bergs, rushed jobs usually end up going bad and I get really upset with myself when I've made an avoidable ballsup through trying to get things done quickly.
One good thing though, when you put it all back together, you can partially re-engineer/reassemble it in the way it should have been done in the first place. Like making access holes/points, using different fasteners, omitting useless bits and pieces, etc, etc.
Just on the airbag thing, when I took mine off it suggested isolating the airbag before removal. I think I took it off once without isolating, so it must be an 'ultra' safety thing. However, when I was taking the ignition switch apart and the pcb, I disconnected the battery as I didn't want to fry the pcb or bugger up the ECU. The rest of what you describe about the top part of the steering column is similar to mine. I also replaced the non tamper bolts with Allan screws - no-one will be nicking my 15 year old motor.