What Forty9 said. A man I knew who operated a gas station used to do the same thing. It helps some. Also you can get a jute or horsehair pad about 1/2 to 3/4 inch thick and put it under the entire floormat (leave it short at the edges so the mat won't stick up). You'll need to cut out for the battery door and the brake cylinder access hole, but it will make most things in there more quiet and warmer in cold weather. Also the rubber stop on your clutch arm is likely to be hard at this age. At least mine is.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end