I just left mine out.
Doesn't seem any noisier without it. Between the wind noise, the fan whine, the exhaust note, and the tranny whine, I can't tell the diff.

It's all music to my ears!

Bell - I've been thinking of adding some dynamatt extreme when I re-glue my rear deck interior panel. Are you able to get a good bond between the interior panels and the foil surface of the Dynamat or is there a technique?
Peace, Ron