Done - hopefully didn't damage the microswitch, nothing seemed to be broken anyway!
Once things are fitted I plan to write up a guide to retrofit the airbag off light and switch, as I've not come across one on this topic yet.
Good news is that I've found the wiring, hidden below the carpet - plugs into the airbag off light perfectly.
View attachment 294522
View attachment 294523
Now got to start thinking about how to program it and drilling the hole in the centre console as well as the side of the dash..