My cold side after the WA/IC is rigth on top of the rad too. It doesnt get very hot at all. But then again, it I havent driven it in the summer time yet.
Anyway, the stuff I got was about 3-4 sheets of paper thick or so. It molds and bends easily though. It if you were going to to inside or out side curves, you will have to do relief cuts to get it to overlap nicely, but if you take your time, it will look just fine.