Well I have struggled with the Ernie Loga pad and it is in. It didn't fit badly but needed to be trimmed in a few places. Since I have a custom installation I needed to make a couple of extra holes. With the felt (jute?) padding this is very difficult to do.
If I had it to do again I would ask for the cardboard without the padding. Then I would glue on the foil heat/sound insulation commonly used on hot rods, etc. Much easier to work with and, I suspect, more effective.