Hi Martin,

Remove airbag then steering wheel, fit clip to secure clockspring position.( clip should come with new switch )

There is a screw you access from under the column cowl, loosen this screw, the cowl with switch attached should release from the column with gentle assistance.

Remove the switch from the cowl.
Fit the new switch to the cowl being careful not to lose the small spacer fitted to one of the screws.

Refit parts in reverse order, this procedure is from memory so may not be 100% accurate.

Regards

Glyn