I used a combination of rhino type spray on bedliner and thick stick on deadener. Placed it all over floor, roof, up firewall under dash, seat, kick panels and up backwall as high as i could reach. Also used rhino on underneath cab, inside fenders etc. Used two heavy rubber floor mats and a thick commercial carpet under and behind seat. Tank is under bed. Also added stick on deadener inside doors and recently added aluminum foil covered insulation behind door panels as shown in link below. That said and done i now wonder why? Tire, road and wind from outside still comes thru the windshield and around doors and produces noise that cannot be completely dealt with. It does cut the "oil drum" effect and is livable to drive with windows up. If your thinking about such insulation to enhance a good sound system - think again. Most fun is to drive with windows down so there's that. No noise when parked