Logical1

Fortunately the 410 and 411 plenum is easy to clean.  2 screws and the slotted cover comes off.  Volkswagen heater hook up hose will direct the water to the ground and prevent any exhaust leaks from  entering the cabin.

My coupe doesn't leak any water.  My tan car leaked so bad it made a pool deep enough to short out my ECU under my seat.  End result was me finally getting around to swapping the turbo motor in.   So not a total loss. 

I posted a fix for leaky windscreen rubber a long time ago.  Use search.   RTV, sharp razor blade [or Xacto] and white vinegar.