I have thought about doing the sludge on top, but im not sure of my install of the dynamat. It all adheared very well in the trunk (not so well in the doors). But it doesnt look like a good job, ive seen dynamat installed where it looks like it just streached over the shape of the trunk and into the wheel well and everything. With mine it was all parts of a roll of dynamat all cut up to fit where I wanted it. So if the install of it wasnt great wouldent that damage the use of the sludge as well??