Dynamat or Fatmat??
I looked into the web site at the beginning of this post and the peel and seal he talked about was asphalt based ice dam material I bought a plastic backed peel and seal called Resisto it is a vulcanized product used for waterproofing under siding and around windows we call it blue skin because that is the most common form we see it in on the job site but the Resisto is red { same stuff tho } it's under 17 bucks for a 18 inch by 50ft roll { about 22 cents a sq ft } and 2 rolls did the whole car with a double layer under the front and rear passenger area in my 69 fastback , there is an adhesive primer for it but I found it sticky enough on it's own after cleaning with tumbler , oh and it's 40mil thick so 2 layers is better than the raaam product I don't see the point in putting a conductive layer under the carpet and behind the interior panels and this stuff can be molded into the small valley's with a heat gun on low if you want I 'm just going to let the summer heat do that I stretched into place pretty good and am not going to worry about a void here and there the jute that comes with the carpet and the carpet itself will build up anyways , there is another product am trying because I get small pieces for free {scraps from the jobsite} and it is about 2 bucks+ a sq ft on a 200 sqft roll= $400+ and is made from shredded tires bonded to a poly mat - no natural fibers to rot or mildew- used for sound as a glue down underlay under engineered flooring it is glued to the sub-floor and the flooring is glued to it , it is a squishy layer about 1/8 inch thick that should provide sound deadening and a little luxury feel to the carpet , with this in the trunk area and the Resisto everywhere the car has gotten a lot quieter inside already and the low resonate hum is gone . my friends car with the foil backed stuff and carpet is still so loud with the headers you can't talk with the windows open without shouting I can already here myself think in mine woohoo