The evaporator in my 93 300E is leaking, and I'm getting ready to do the replacement. I've spent the requiste time reading up on the procedure in the tech manual and this forum, but I've still got a couple questions:

1) I'll obviously need to evacuate the r134a before doing the replacement, but should I completely flush the system? I'm worried about the amount of oil... some oil has probably leaked, and it seems flushing is the only way to gaurantee that I have the factory spec qty in there.

2) What oil does this car use? I understand its PAG, but it comes in three weights - 46, 100 and 150.

3) Several people have said its a good idea to replace the 'vacuum elements' when doing the evap replacement. What are these, and how much longer does it take to do this as well? Can anybody give me a part number (numbers?) for what I need to buy...?

4) The MB Tech manual says to apply 'sealant' to the sealing surface of the a/c box (step 18 on procedure 83-554). What sort of sealant should be used here?

5) Anything else I should replace/worry about while I'm in there (seals, etc.)? I really don't want to have to open this thing up again in three months when something else goes wrong....

Wish me luck...