How hot do our exhausts get near the exit?

Just installed my SVO/Borla side exhaust kit yesterday and due to clearances it'll occasionally knock against the seam where the rocker panel and underbody are joined together--you know, that strip of metal where the stock plastic rocker panel covers is riveted to. Usually only happens when starting the engine, and I guess the rotation of the engine causes the exhaust to move slightly. It's just the pipes near the tips, obviously, that clang against the seam. Rest of the system is fine and clear of the body.

Anyway, I was wondering if I could fasten some kind of material there to minimize the clanking sound when it happens (don't want to be too ghetto). Obviously whatever I put there would have to be fairly heat-resistant. I was thinking of something like the silicone used for cooking utensils and such, if the pipes don't get too hot there. Or maybe just shoot some silicone like aquarium stuff. Would that work? Any other bright ideas?

Thanks!

Hmm...unless they pretty much just weld the hanger from the exhaust to the undercarriage (locking the pipe in place) I don't see the point in having another hanger. It's just the 1/4" or so of clearance between the pipe and the rocker panel that's the culprit. I'm just hoping that putting some kind of buffer there will minimize the rattle.