The first step was to remove the steering column shroud, which is held by three screws. One is underneath and the other two are behind the steering wheel, which are only exposed when the wheel is turned a 1/4 turn, both ways.
To separate the top and bottom halves push the upper edge of the bottom half whilst simultaneously pulling downwards, which will release the clips. Do this for both sides. All the controls remain attached to the column.
The bottom half will need to be manouvred over the steering column adjustment button.
To remove the lower plastic panel that contains the light and diagnostic socket there are two screws that need to be removed, one at either end:
There are also two clips along the top edge and a slot that engages with a small bracket at the back of the panel. Once the screws have been removed and the clips released the panel should be moved slightly towards the front of the car to release it fully.
The slot is below the yellow tape and the bracket is at the top of the picture.
This shows the position of the clips:
Next, disconnect the courtesy light and diagnostic socket, which are both bayonet fittings. Mine also had a little button (something to do with alarm?) on the right side which had to be disconnected.
The panel above is held be two 10mm headed screws on the lower edge:
The top is held two 10mm headed screws, plus a Phillips screw. One screw is in the Parking Brake Release handle recess, but is accessible:
Another is below and left of the ignition switch, so the switch cover needs to be removed. It's held on by three clips, but take care to lever behind the plastic backing and not the foam covering:
The Phillips screw is tucked away behind the coin tray. It's the middle one:
Having removed all the fasteners the panel can be eased away, but as ever, there are electrical connections to dealt with. There are the connectors to the fuel flap and boot release switches:
Underneath the switch assembly is the bonnet release, which is held by two screws (this is where a mirror was useful):
And on the left is the electrical and tube connections for the temperature sensor:
And now the panel can be removed:
This is the sight that will greet you:
The air distribution tube is easily removed - it's just a push fit, although it's easier to disconnect the left side first.
As I said, my aim was to replace the brake light switch, which was achieved without lying upside down in the footwell or removing the front seat.
Good luck!