The chrome cover attaches to a support that is popriveted to the body behind the cover, so you must take the chrome parts off before you can remove the bumper cover. You must remove the tail lights to disengage the chrome part fasteners from the popriveted supports (the tangs on the pins will probably break if they are not already broken). When reassembling, you can probably use a tight O-ring to keep the chrome fasteners in place if the tangs are broken. An alternate reattachment method is to make a hole where the pin is, and use a tree fastener through the hole.
There are two nuts on each side that hold a plate over the mounting surface of the cover. You will also find 5(?) fasteners on the bottom of the cover, as well as the top, and maybe a couple of screws in the corners of the gate opening.