For whatever reason, water leaks inside my cab when the AC has been turned on, and only when the AC has been on. I think it's something with the condenser but I can't seem to find the drain location. Any ideas?

 

There should be a small black hose that drains the condensate to the underside of the truck. It is on the right side as that is where my condensate comes out on the ground.
Passenger feet might kick it loose. look there.

 

Drain hose can be clogged too, push a blunt ended wire up it to see if a whole bunch of water comes out. It is located more toward the passenger side.