First, take out the shifter trim panel and shifter boot
Second, remove the vent grilles by carefully inserting a small flat screwdriver between the grille and the trim panel and GENTLY & CAREFULLY prying it out
Finally, once the vents are removed, look up inside where the vents were, you will see two little plastic arms that hold the trim panel in place. Use a very small screwdriver, punch, or similar device to gently pull each of the little arms downward, thus releasing the trim panel. it should now pull right out.
Good luck, hope i didnt confuse you too much. You will see what i am talking about (the little arms) as soon as you get the vents out.