Assuming yours is not too much different than an A body, it's not that bad of a job to rebuild the whole heater box with a kit from DMT. Why do you think its the evap?Did he actually check it? That's the most protected part of the system. It's more likely a fitting, or the condenser. I just had my valve cover off. Have to lift the AC line pretty far to get it out. Praying it didn't open anything up moving those lines after I finally got it charged and working.
