The small cover has a lip that fits over the rear of the plastic hanger piece. You will have to pry the lip out from the rear plastic and work the vinyl cover up over the plastic hanger. Then you can remove the screw securing the hanger. Just have to be careful removing the vinyl cover so as not to break the hanger.
I can email you a picture of the hangers apart if you need one.
Dave... Its simple, the peice you are seeing is a cover. Just slide that off, there is a hard platsic part underneath that has a screw. Its like a bumper with a bumper cover.