With the '57 interior bare and going from nothing to complete new interior and carpet am thinking would like to put some sort of sound & heat barrier down on the floor. Maybe the door and rear seat interior cavities? The floor was cleaned and sealed but would like some sort of dense mat applied to the floor. Not at all familiar with all the offerings today but thinking now is the time. Would appreciate any tips, info and real world experiences with what to use and what not to use. See some offerings on eBay but just don't know enough about it to choose what to use. Thanks for any help.