How do you replace the rear bumper fillers on a 1980-1984 Cadillac Deville/Fleetwood?

I have a 1984 Cadillac Coupedeville that needs replacement bumperfillers, but I have no idea really where to begin to take off the old ones. I was wondering if anyone had one of these Cadillacs that had this issue with those back bumper fillers?How do you replace the rear bumper fillers on a 1980-1984 Cadillac Deville/Fleetwood?It can't be that bad, just look for the screws..

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