Actually, Mike, I don't know how well it works. A friend of mine recommended the Kilmat because he has used it and likes it. Roger Spears used some stuff called EZ Cool in his '33 and says it's good. It has the foil on both sides of closed-cell foam. Maybe some other folks on here can give you better guidance than me. You are probably going to need something before I get on the road and able to say good or bad on this stuff.

Body filler is good for filling countersunk screw holes in wood, too. Sink the screws, spackle the holes with body filler, sand and paint. The screws will never back out of the holes!