I was able to get it out. The plastic top was held down by some wonderfully sticky tape. It took persistent pressure but a few sections gave in eventually. Once that is off you can easily remove it.
The screws take a #2 square drive.
Whoever put in the weather stripping around the AC was sloppy, most of it was wadded up and the adhesive backing hadn't been removed.
The screws take a #2 square drive.
Whoever put in the weather stripping around the AC was sloppy, most of it was wadded up and the adhesive backing hadn't been removed.