Disconnect the battery, go inside and make a cup of tea This is to
allow the capacitors or whatever to discharge.

Unscrew the bolts holding the air bag unit on using an appropriate
torx tool in the two holes behind the spokes of the wheel. Lift off
the airbag and unplug it from the wheel. Haynes suggest doing this
gently and without undue shocks and keeping your head out of the way.
Then lay the airbag unit where it won't do you a mischief if it goes
off accidentaly.

Then unplug (or is it remove the connector from the mounting?) the
wiring on the wheel then remove the wheel as per normal. If you forget
to unplug the wiring on the wheel you will have to repair it with a
soldering iron when you accidentally pull the plug off the wire when
you remove the wheel. BTDTBTTS.

Removing the steering wheel makes it far easier to remove the
intrument panel to get at the bulbs; so do those whilst you have the
wheel off.