What I would recommend is getting some spray foam and filling the braces of the trunk lid. But don't put to much it expands alot and cut off the excess. Then go over it with deadener. I would put a layer on the underside of the rear deck, 1/4 panels, backside of the liscence plate, backseat braces,the floor. ANd if you still have some left go for the wheels wells and put another layer on the 1/4 panels, trunk lid, and then any place that doesn't have any. Make sure you use a degreaser or dilluted laundry detergent to clean the surface or it won't stick. I didn't degrease my trunk lid the first time and half of it fell off.