01 DTS wet carpet

I have a 01 Deville DTS and the front carpets on both sides are soaked. I'm assuming its condensation from the evaporator or maybe plugged drains on the cowl. I'm puzzled on how to access these drain areas to clean them out.  

Drain located in engine side compartment on firewall . It is a rubber elbow you will find it on right side above steering gear. Does car have sunroof?

Yes in does have a sunroof. I assume I will have to either jack the car up or have it put on a lift for access.
I'm am familiar with the older Caddy Devilles from the seventies and eighties but not the newer ones.
I had to replace the blower motor about four months ago, thar was a chore in itself.

I would check sunroof drains also. Drains are located in all 4 corners of sunroof lower tray.Front ones are easy to see and the rear ones you can't.They're hoses attached to each which allow water to drain under car.To check them, fully open sunroof and you can trickle water from 1 or 2 litre bottle into tray and look for to run on to ground in 4 places. Drains normally cleared with compressed air. If drain(s) is blocked, REMOVE as much water as possible prior to blowing out drain(s).Then recheck. With a/c assumption is correct.

Thanks slowroll, will attempt solving problem within the next couple of days.