I used Frost King Duct insulation. It was recommended in the ERA manual.
http://www.lowes.com/lowes/lkn?actio...929-1410-FV516
Self adhesive foam on one side and foil on the other. Very easy to work with. I used it through out the cockpit (don't forget to do the firewall all the way up to the body) and the trunk floor.
Matt