Take a look at the top of the cover. See how there's a "U" shaped spring held down flat on top of the cover by a plastic tab? Pry up that spring with a screwdriver and tilt it up. Make sure the latch at the front of the box is unclipped and then reach back as far as you can on that "U" spring and squeeze it together while lifting it off. This will disengage the ends of the spring from the fuse box and allow you to remove the cover.