Work completed on a 1995 Nissan Hardbody XE-V6 4X4.
Tools needed.
1) Stanley socket set fount at wal*mart.
2) shop knife.
1) remove blower fan. refer to How To R&R Blower Motor.
2) remove glove box. Left and right glove box hinge. Remove the pins.
3) Once the glove box is removed you'll find a metal plate. remove this plate. 4 screws, one at each corner. There are aligning pins. Be gentle when pulling out. Slightly move the plate back and forth.
3) Remove electrical connector in front of a/c evaporator.
4) remove sensor.
Look what I found.
4) remove 9 metal retaining clips. There on all 4 side. Removing the clips in the back was PITA. FYI only the front clips got reinstalled. i used a flat head and a dull shop knife to remove these clips. Watch out, they go flying when popped off.
5) remove bottom half of evaporator housing. Take your time and be gentle. It's not going to drop down easy. Try not to brake anything.
This is what I found. 
6) clean out pan.
7)all done
edit from GTPhill
Rather than snapping out the lower pins of the glove box, a much easier way to remove it is to pop inwards the two round posts that keep the glovebox from falling out. Both of those posts pop inwards with light pressure from a screwdriver, causing the whole glovebox to hang down, and exposing all of the needed screws.
Its clear this is the way that the original glovebox was installed, by screwing in the two lower glove box brackets, then raising the glovebox up, and then popping in two of the round plastic track retaining pins.
