[Vwdiesel] Rabbit leaks water

[Rudy]

I'm trying to chase down a water leak in an 81 Rabbit on the passenger side.
When I reach up under the dash and behind the glove box there is a little
water on the tube for the air vent.
 
I think the water originates in the front and runs under the front seat to
the rear floor.  Would some of you guy's relay some of your experiences?
I'm running out of places to look for sources.  Thanks
 
Rudy