Hi Dan
I searched for pictures but did not really take any of the dynamat install. Sorry!
My cabin floor was finished internally in a heavy coating of red oxide paint,.
I covered the floor and the upright sides of the tunnel with a single coat of Dynaliner , and wrapped the rear firewall and footwell area as far as practicable to the midline . I considered doing the doors but decided against it due to the additional weight , but note Larry's positive comment. The clearances inside the doors to the mechanisms are tight so you would have to carefully choose the location for any matting.
All of the floor areas were also covered with a 12mm Dynaliner foam matting, under the carpet, in addition to the single layer of Dynamat . The rear firewall area was covered with a 3mm Dynaliner over the Dynamat and I also adhered 3mm Dynaliner directly to the roof metal by itself under the roof lining.
The Dynamat has the potential of coming loose if adhered directly to the underside of the roof and its a very hot day . In addition its too heavy to want to put it up high anyway and not required IMHO.
I cant say its quieter, as I don't have a before experience to compare it to, as 6997 was not running when I got it .
All I can say is its still pretty loud in the cabin but is significantly quieter than standing outside , as at least you can talk to another person if your inside the cabin. No chance outside !
There appears to be no floor or roof resonance to speak of now this has been done .