Hey guys, I just converted a 48 qt Igloo Icecube cooler into a MLT using a bazooka tube, bulkhead and SS ball valve. It's nice and water tight and I'm just about ready to use it. I had a question about the hollow lid though. Has anyone ever used low expansion foam to insulate it or is it even worth it? Drill a couple of holes and fill it up? Any ideas or condemnations welcome.