The A pillar trim pops off by inserting a large flat blade screw driver underneath the trim and prying at top and bottom. There are two small metal clips on back of trim(top & bottom). Don't loose the clips. They insert into two small oval shaped openings in the body A pillar metal. To reinstall just pop it back on using your fist. One other thing, if you need to remove the windshield I would recommend the purchase of a genuine Mercedes windshield rubber. The aftermarket brands simply do not fit properly.