Dynamat is good stuff. You guys are smart to put it on while youre at the stage you are. Painting it to match is an awesome idea, I have found that any bit of the the raw shiny stuff really sticks out like a sore thumb.
In converting over from 727 to 5 speed tranny, I got new carpet. While the carpet was out I had some down-time and I got to thinking about the noise level and heat that comes up from the floor. I went to home depot and they sell an insulation material that is aluminum on both sides with air bubbles in the middle.
Because Im a cheapskate, I went online and instead found some similar material that had a closed cell foam layer instead of air bubbles. Supposed to add aother 19db of sound suppression. only 1/4 inch thick. Might not be as good as if I had covered whole car in dynamat (which would be nice), but I bought a huge roll of this stuff, enough to do the Challenger and my 4Runner and it was very cost effective. http://www.insulation4less.com/highr_FfmF.asp
I placed a double layer agaist the the backseats, complete edge to edge single layer along the floor and behind the door panels and all interior panels. I stopped where the carpet stopped along the firewall though. Carpet lays flat and door panels all fit and line up with the stuff installed no hassle at all. I used the special tape to seal all the cut pieces togethe and in places I sprayed a little 3m spray adhesive here and there to shape it to the body lines.
(It should work pretty good for heat, I was roasting away installing that stuff as it relfected back all my body heat and the heat from the light bulb. (it was over 100* in the garage that day too, whcih Im sure didnt help. hahaa)
anyway heres a snapshot of the back area
