I've not seen how the mirror is attached on the Taos but in general, there is a small metal wedge that is glued to the glass. the mirror attaches to the wedge with a set screw of some sort. that allows the mirror to be placed or removed without harming the wedge. seeing as this is a VW product, you might not need to remove the wedge, the new mirror may fit on it the same as the old one.
in the case you need to remove the wedge, a flat razor blade for scraping paint, etc. easy to find at HD/Lowes/etc. the glue doesn't stand up to being scraped off.