1990 Jaguar XJ6 Rear Bumper

I damaged the right side piece of the rear bumper that wraps around the corner of the car and goes along the lower quarter panel terminating before the real wheel well. The side marker light is installed in this piece. Some parts sites that I looked at called this the bumper blade. This attaches to the inside of the bumper at the corner and has 2 pins that slide into a guide block attached to the quarter panel. It appears that the only way to install this is to remove the entire rear bumper, attach this piece, then re-attach the entire assembly to the car. I found 2 large bolts on the underside of the bumper that thread into the "shock absorbers" that attach to the car. I can't find anywhere else on the car or in any drawings any other place that the bumper attaches to the car. I removed these bolts, but the bumper won't budge. I need to know if the bumper just needs a little "persuasion" (because of the age of the car), or, ideally, if there is another way to attach this side piece.