These are a royal pain to remove! There are three plastic keepers located along the bottom edge of the cover, easy to see. There is a tab on each white keeper (see picture below) that must be depressed while sliding out the white keeper. The three on the bottom are fairly easy, the two on the upper/outer edge are tricky.
I removed the top bumper cover (the one you would step/sit on) it pulls straight up, no tools required. With a flashlight you can look down into the small slots (that the bumper cover snapped into) and see the white keepers, I used a long skinny screwdriver to depress the tab and at the same time shove it to the side, where it fell into the cover area. Once the cover was off the tabs were easily recovered.
Getting them back on was a feat! DVR's side no issues, long forceps eased them right in. Pass side the outer most one, forceps, but the inner one No room whatsoever so .......hole drilled, easy as pie after that