However the 307 is different. Switch off the ignition. You do not need
to disconnect the battery. Leave the key in the ignition as you will
need to turn the wheel. Look at the back of the wheel and you will see
two small holes at three and nine o'clock ( with the wheel straight).
You need to insert a rod in through the holes in turn and feel for a
clip that is sprung. Push against the clip while pulling on the air
bag. That side should come loose. Repeat on the other side and the air
bag should be free. To disconnect the plugs, look at the plugs top and
bottom of the air bag. You will see a locking tab which needs to be
lifted up (use a small screwdriver). Then gently pry the plug off with
the small screwdriver. They are colour coded green and blue. Then pull
off the earth wire.
You will see the earth terminal on the wheel--two wires going into a
metal thingy that is just pushed into a square hole. Dig it out and
cut it off close to the metal. Then crimp both wires into a round
terminal. Just below where the earth was is a slightly raised round
bit. Drill a hole straight through the wheel being careful not to
damage the shroud behind covering the Comm 2000. You then need to
screw the round terminal to the wheel with a self tapper (1/8th hole-
1/8th self tapper) just long enough to go through the wheel but not to
touch the shroud. Make sure it is tight. That's it. Replace connectors
on the air bag, line it up and push back on to the wheel. The horn
will probably sound as you do this!!

If you are feeling adventurous, because of the aluminium filings
getting everywhere when you drill the hole, take the wheel right off
and do it outside. Just disconnect the flat plug (note how it is sited
in the wheel) remove the centre bolt (Torx 55 ), and with the flat of
your hands, hit the wheel firmly at opposite points of the wheel a few
times until it comes loose. Note the lining up marks behind the centre
bolt.

Good luck. Anything that is not clear just ask. I know it is difficult
to explain like this but I hope you understand. As long as the
ignition is off when you disconnect or reconnect the airbag you will
have no problems with the airbag going off. I have done countless of
these mods with no problem at all.