What about fabricating fiberglass or kevlar panels the shape of the aluminum? I saw a 2011 Hemi Challenger that used kevlar tubing in the intake system to prevent heat transfer to the intake air. The same principle could be used here. I've seen a few dashes and tranny tunnels etc covered in it. Same idea, pretty cool look on the inside too. A spacer and rivets would hold it in place. A REALLY crafty person could probably fab up an insert that slips in in one or a few pieces for a nice clean look. Very little heat transfer. They're light weight and could be painted to match, contrast or accentuate the engine bay or painted a chrome, polished aluminum or copper colour.

Daniel