I did this on my 03...I liked the look of the chrome caps too.
You get a small screwdriver, and carefully pry up on one corner of the old cap (I started down by the bottom....) get your fingers behind it and pull it off. Pull straight up, because the "hooks" that hold the covers on, they are very fragile. You'll probably have to take some old tape pieces off (it rolls up with a little help from your finger)
Wipe off the back of the mirror, peel the plastic from the new cover's tape, and press the new cap on.
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