[s-cars] Any secrets to uncloging drains?

[hoog23 at aol.com]

Spent all week drying my car out from last weekend only to find the floors (driver more than passenger side) soaked this am after heavy rain last night.
 
Since it is still raining I brought car home and kicked the other car out of the garage.  I opened up the plastic cover over the cowling to find a pool of water on the passenger side (opposite glove box).  Could also see a small stream running down carpet in passenger foot well.
 
I cleaned out the drains best I could last year but couldn't really get at the one under the (blower motor?).
 
Does anyone have any tricks to getting this one clean?  I even tried using a long thin vacuum nozzle.  Maybe compressed air or make friends with a midget?
 
Thanks,
Dave