Replacing the evaporator is a royal pain in the ass. The whole dashboard assembly and everything in it needs to come out of the vehicle. I would not recommend anybody trying this unless you have plenty of time and patience. I found a white piece of foam inside the evaporator case that I believe was intended for vibration control. In my case it seemed to block half the cooling fins (less airflow= less efficiency) and prevent proper water draining (probably contributing to corrosion and failure). This is likely installed incorrectly in other vehicles, and obstructing the drain hole causing wet carpet.