Disabling Airbag

["Mittal, Vikram (SUPP)" <Vikram.Mittal@supply.ge.com>]

I would like to disable the airbag in my 1990 Audi 100.  My wife is 
5' 1" and I am always concerned since she sits quite close to the
steering wheel.  

I have considered pedal extenders but then since I am 6' tall it
would be a problem when I drove the car (I think).  The best solution
would be to either

1. Disable the airbag permanently
2. Put in a switch

If anybody know how I can do either, please send me the directions.
Thanks.

Regards,
Vikram.