So, I swapped out the old rear bumper impact strip for a Ziegler part.

I had to remove the rear bumper cover. This involves removing 10 nuts located inside the trunk. Two are located in the middle and are readily accessible. There are two on each side at the back and two on each side in the cargo wells on the sides of the trunk. The stiff trunk liners in the wells are removable and taking these out gives you access. I had to pull out the CD changer too. Also, there is a soft plastic piece on each side that attaches to the "front" of the bumper cover at each wheel well. These pop on and off.

Once off the car (and on an old blanket for protection), the next task was removing the old impact strip. There are three philips head screws that hold the parts that wrap around the side of the bumper cover. I then used a utility knife and cut off the triangular raised bits that lock the tabs that pass through the slots on the bumper cover. The old cover came right off. I used some foaming grime cleaner to clean the bumper cover (which also provided some lubrication for attaching the new impact strip).

I then reused the foam piece that's under the impact strip and pressed the impact strip into place by inserting the tabs into the slots (after double checking that I had the piece right side up!). A couple of smart raps with the palm of the hand worked fine.

Reinstalling the six screws took some work. I used a small screw driver to pull the drilled-out posts that the screws go into close enough to the holes in the bumper cover for me to get the screws going correctly and then tighten both sides down. Reinstalling the completed bumper cover was reverse of removal. I had someone help me reposition the bumper cover, which made things easy.