Looking for a rattle.

I made an account on this forum because I often come here for ideas and help with common mods. I drive a blue 2006 xrunner I already have a head unit, amp, subs, all kinds of custom LED interior and exterior lighting. I have a very distinct metallic rattle that sounds like Tin cans dragging along under the passenger door. I read that people have found the culprit as a catalytic converter heat shield that's around the actual cat. But once I shut off the truck and crawl under it, this is not the case. The rattle which has now evolved into a clanking sound is driving me insane. If anyone has any ideas or tips or has had a similar issue I am open to suggestions. Thanks in advance. I'm also looking for the front valance for the xrunner without paying 750 for the Toyota OEM valance. I found one on carid from VIS Racing, but I don't know how well it would fit.