NO! NO! NO! Don't EVER disturb one of these evaporators unless it IS INDEED leaking!

Contrary to popular belief, all of them do not fail. They have a terrible reputation, but that means probably a 20% failure rate. Disturbing one that is not leaking is asking for trouble.

The evaporator in my '88 300E has been in there since they built the car around it in 1988 and it is still as tight as it can be. I did a podectomy and had the dash out in 2004 and left my non leaking evaporator alone.

If it ain't broke, don't fix it!