I pulled the old and very rotted headliner out of my 69 the other day. I got a ton of brown powder that fell out as soon as I started pulling the edges loose. The powder was from the brown insulation?? that is attached to the under side of the roof. Most of it will just come down if you just rub your finger on it. What have you folks done as far as replacing it. I was thinking about possibly dynamat or spray on undercoat. I would worry that the dynamat might be too heavy and possibly bow the top or just fall down eventually. Any suggestions would be appreciated. Thanks.