Seems like it came from the rear seat or rear door area and I'll be damned if I can figure out what it is. I did have my rear doors apart. I was putting the rear set of the door panel fillers on from Bruce @Hush Car Audio and also the Second Skin on the rears. The panels fit really nice, just like the fronts did. It has definitely quieted the truck more. I took a before picture and then forgot to take the after picture. It's way too big to be my di** protector and my nipple covers are still on! A cap for something, just wish I knew what.