Rattling noise in trunk

I hope I'm clear in my request here...kinda tough to describe.

I've got a clunking/rattling noise which is coming from my trunk whenever I go over a bumpy road; passenger side to be more exact. After trying a few things to find the exact cause, I've determined that it's got to be that carpeted side panel bouncing up against the metal.

I know there's a clip holding the carpeted panel to the rearseat frame...I bent it a while back during another operation. I went to the Ford dealer today to see if they had a replacement, hoping it will help stop the rattle.

While the guy had the diagrams up, it was difficult to find the exact clip. But it also showed a wingnut that screwed onto a stud at the top of the carpeted panel, securing the panel more to the body. I never had these wingnuts. Does anyone else have them? If looking inside the trunk from the top, it would be under the lip of the side opening.

Am I being clear enough? Like I said...it's a little tricky to describe.

I'll keep that in mind if this theory doesn't pan out. Thanks! The noise doesn't occur when I get on the throttle; it only happens when going over not-so-smooth roads. Even some of the slightest imperfections in the road will make it happen. I'm pretty sure something is just jostling around in the actual trunk, but I'm open to anything at this point.

I have had that one side panel out of the car a few times. Last year I changed the shocks, so of course I had to take them both out. A couple months ago, one of the adjusters for the shock broke so I had to take the panel off again to replace that (I have Tokico D-spec adjustable shocks on there). And last month it was off again to change the taillight. So it's seen a bit of moving around.

I suppose it wouldn't hurt to have the bushings checked out all around seeing that the car's got nearly 91K miles on it now.