Isn't replacing the evaporator listed at about 17 hours in the flat rate manual for some of our cars ?
I think I would turn my car into a parts car rather than tackle that... under dash stuff always kills me anyway... too big and too old for that anymore.

But I am going to clean my evaporator when I put the AC back into my 240...but I swear I am going to figure out a shortcut.... pictures at 11.