I've done it to my '8:
I used an 'adapted' door switch and a license plate light fitted into the 'roof' of the glove box.
(First try was a failure due to the fact I used a normal interior light - which didn't have any shade
in the direction of the person opening the glove box lid. Second try was a success when I'd
found that Hella plate lamp - that only shines down (and in) but not straight out towards the
eyes of the passenger. Something to think about...)
PS
There is an auto detect feature in this that tells if the switch have failed:
The switch doubles as the glove box alarm detector - if it fails the alarm will act up and report...
[8D]