Remove the screws for the handle in the armrest.
Remove the inside door handle.
Remove the screw up by the A pillar.
Grab whichever corner you can lift free the farthest and pull sharply. By pull sharply, I don't mean just try to rip it off. Try to pop the clips out of the door (not the trim panel) by pulling on it and keeping it as flat as possible. It's kind of tricky and you have to have a feel for it.
If that sounds too tricky, get a trim tool (NAPA has them) and use that to pop them out of the door (NOT THE TRIM PANEL!).
Some folks can install the mirrors without removing the panel, I couldn't. Good luck.