I did pull the shock tower/back panels out a dynamat what needed to be. Baically open cavitys, and places that didnt have any. Theres alot of factory deadning back there to start with. I'M going to glue carpet padding to the back of the cover to block out even more road noise and also to make it a little heavier so it doesn't vibrate from the bass but its pretty quite the way is. As far as rattles I really don't have any excpet for the hatch that I havn't dynamated yet.