Right, I was aware from previously looking for this stuff that the early cars didn't have them. All I'm after here is where to find the material so that I can make one how I want it. I'm looking at the fatmat's site right now, compared to the dynamat stuff, and there seems to be two choices - one is the foil wrapped stuff that reflects heat downward, and the other is a black urethane that absorbs heat upward. I'm not really sure which would be the best way to go, so the third option would be to find whatever this padding is made of that isn't foil wrapped that doesn't reflect or absorb heat - it justs acts as an insulative barrier. I've seen it done at past car shows I've been to, and it looks awesome - I just don't know where it came from.