Chevrolet Repair: ac evaporator drain, ac evaporator, water sound

Question
I have a 1995 s-10 blazer and there is water sloshing around under the dash or floor. I have tried to find the evaporator housing drain but cannot. I have put additional holes into the unit that I believe houses the evaporator unit itself. No luck. I took apart the cowling under the dash and drilled holes into everything I could see. No luck. No water is coming into the interior of the car and no water is leaking on the ground. I live in Florida so I use it daily. I took off the front wheel and the fender skin and still no sign of a drain. As you can see by now I am desperate.I am very mechanical in nature and have searched the web but no one can tell me where the drain is. I used a mirror and flashlight and still no help. I am going on the assumption that the ACTUAL evaporator unit is NOT under the dash but under the hood just after the dryer canister. This may not be your expertise but maybe you can point me in the right direction. I can't find a book that I would be more than willing to buy that will help me. Thanks in advance for your advice.
Dave

Answer
Hi Dave,
Sorry about the delay...I couldn't even access all experts till today.

Have you explored the possibility that the gurgling water sound might be air in the heater core?

I think the evaporator drain is just a notch in the housing, where it contacts the firewall.

Van