You have to pull it off!
I used a very small flat blade screw driver wrapped in a bit of cloth to help it along.
take the mirror of, then you can unclip it without damaging the clips.
I did it last night.
Lol i took off the mirror then started to pull the cover off, i bottled it, felt like it was going to snap. It was ph2 so i assume its the same. Is your mirror loose inside or something ?