Hi,
In order to remove the evaporator, the entire instrument panel(dashboard) has to be removed, then remove the hvac housing and separate housing to remove the evaporator. To give you an idea of how long it will take, book labor is right at 10 hrs.
Here are specific directions(pdf file format):
Instrument panel: part1 part2
HVAC housing
evaporator
Automotive Repair Shop Manager
Automotive Repair Shop Manager, Technician/JA Mentor