1995 S600 A/C Smell

[pcmaher]

I have a 1995 S600. I believe that the front A/C drain hose(s) are plugged. Air blowing from the vents smelled like wet dogs when I first got the car. Driving with the heat on full blast seems to have helped some, but as soon as I start using the A/C again, it comes back. I do not notice water dripping from the front of the car when the A/C is on. I do see water dripping from the middle of the car, but only when the back seat A/C is in use. Also, turning on defrost immediately fogs the windshield up. Can someone tell me where the drain tube is located, and how to clean it out? Any info you can supply is greatly appreciated!