If you open the glove box and remove its contents, there is a large black "door" secured by a tab (on the right, as I remember) that you'll see makes up the rear of the cavity. Open that, and you'll find a smaller secondary door with tabs on each end. That covers the filter itself and is tighter-fitting. Take that off as well and you'll see the side-view of the filter.
The filter slides out; note the proper direction of installation and install the new one in the same way.
This shouldn't take more than 5 minutes; install on these is a breeze. Mine seem to be good for a year or two.