Looking for some advice on sound insulation for the new engine hatches we made for my 31' BHM. I've got some pretty heavy lead-core stuff in my DMR, which came w/ the boat and does a hell of a job muffling the 671's. It is about 2" thick with gray foam on each side of a core material and a silver foil on one side. I guess that's what I'm looking for, but first I need to know exactly what product it is and where to get it. Or if there is anything else as good or better. In the BHM, the engine is right underfoot, so even a little 4 stroke diesel makes a lot of noise.