BJ's Offroad Underhood Insulation--which side up?

[drlocke]

I received the three underhood insulation panels from BJ's in timely fashion, and they are looking good. They have a sort of "rind" side that is much harder and smoother than the other side, which is merely the fiber itself. Which side goes to the sheet metal under the hood?

Part of me says leave the smoother side toward the engine, as it is less apt to snag and tear on things than the other side. The other part of me says put it up toward the sheet metal, as it provides a better substrate for the adhesive, making the panels less apt to tear off the underside entirely.

Which way? I didn't find any instructions packed with this material...

[REDONE]

The factory type was wooly side to the metal and hard side to the engine. I only know this because I've never found an easy way to remove the remains of the stuff from the metal. It stays hairy until I break out the sander and remove it all including the paint.

[billyrb]

correct, shiny side down

[drlocke]

Thanks! I propose using an aerosol-type contact cement with which I've had great luck with before in making flexible patches that remain tough under adverse conditions. I hope to be able to provide enough saturation of the woolly surface that the adhesive doesn't simply absorb back away from the interface where it needs to be present to do its job.

I'll go with whatever is advised, but--FYI-- I must say this contact cement spray I've used for 30 years, and had admirable results.