Help with rattle in tub?

[YosemiteSam]

I've got an MQ dual cab with tub. A few months ago I needed to remove the sports bar to mount a deck lid. In the process I dropped part of a bracket - about six inches by half an inch steel - down inside the wall of the tub. Above the driver side rear wheel. After quite a few gravel roads a rattle has developed right about where the bracket fell in. Maybe it's coming from the lower section of the tub right in front of the rear wheel. Thereabouts at least.

So is there any way to fish around inside the tub wall? Is there access? Or do I have to live with the rattle or remove the tub to get the bracket back? I can't find tub schematics anywhere to see how they're put together.

Note: I'm guessing it's the bracket. It could be a part coming loose that I can't yet locate though I have had a good feel around. The truck is six months new so I doubt any parts have rattled loose yet.

[WUNSIE]

Can you remove the plastic inner wheel well guard and using a magnet try and snag it so it can be retieved, cant see it being stainless so a magnet will stick to it, shine a light in there and you might even see it

[YosemiteSam]

Thanks. I’ll give that a go. Are those push pull clips holding the liner in?

[WUNSIE]

Yeah pretty sure that's all, might be a screw holding the mudflap on, sorry not able to suss mine out at the moment champ