Chad,
I think I have some data on the system and will share it with you when I am back in town next week.
I completely removed my system as Scrap described for a thorough cleaning and service. It was simple and done without surprises.
One thing I recal was you should have the selector in a specific setting (full defrost ?) before dropping the assembly from the firewall. That is the piece I can't remember...
More to follow,