The mirrors themselves pop right out...they are held in by a ball and socket joint ....go easy and try to avoid breakin the mirror. Its a good idea to remove the entire assembly. At the bench, clean all contact surfaces and grease all parts. You want to use a good water resistant, tenacious (good staying) grease....good choice is syl-glide (this is flexible at very cold temps, water resistant, very tenacious)

Note on syl-glide....silicone grease is NOT a good choice for critical high pressure applications (wheel bearings and such). For those applications, you want to use a good petroleum based lubricant. But silicone grease is one of the best choices for low pressure "slide paste" applications....mirrors, sun roofs, throttle linkage etc., and for lubricating rubber parts (installing bushings, protecting rubber seals etc.) as it doesnt degrade rubber.

__________________
1984 300TD Wagon, 407,800 mi (current daily driver)
1985 300DT Sedan, 330,000 mi (gone to that great autobahn in the sky)