I found out this week that the evaporator in my '87 300e is bad and this is where the freon and some compressor oil is leaking out. I about choked when my mechanic told me that the job is approx 14 hours and includes removing the dash. He also told me that a MB evaporator is about $900.

Has anyone ever replaced their evaporator with a non MB part? I found one online made by ACM w/ valve and it says OE for $200. Will this work, and if so, why is the price so far off the MB part?

Should I replace the heater core while I have it out of the car? Any other sugestions would be a big help. Thanks in advance.