Take the shelf out. Then I think there is 1 or 2 nuts on the engine side of the firewall that you take off, so the evaporator unit will come out. I think there might also be a screw holiding the evaporator ducting to the heater box ducting. It really isn't hard to figure out, if you start looking at it.
There are also some wiring components and some wiring that you can remove from under the dash. It is all plug and play, so just unplug it. Remember to plug the blower fan back in, otherwise it won't work.
There is also a switch on the hot/cold selector that is part of the AC, it can be removed along with the AC on/off button in the faceplate.