-the Central part of the rear bumper is attached by latches to the amplifier. It is easier to Unscrew the nuts on the bottom side and remove them together with the amplifier.
-to remove the side parts of the bumper, you need to:
-remove the screws in the wheel arches.
-screws on the bottom side.
-Unscrew the nuts that attach the sides to the wings (you will need a long collar).