I want to insulate the inside of the firewall and the floor of my '34 to keep some of the engine heat out. I ordered some black jute with foil on one side only from LeBaron-Bonney but they sent me a roll with foil on both sides since they no longer carry what I ordered. They are letting me return it with full credit. I can't find anyone else who carries the black, one sided foil. Anyone know where I can find it or do you have other suggestions? I don't want it to be noticeable.

Glue on some black vinyl to one side. Or glue to black upholstery cardboard like the original firewall pad used on some Chevys of that era. The rubber mat should cover the floor.