School me on the correct way to do this. If I don't tuck it behind the sheet metal then it will cover the teeth that I assume are there for the headliner to grab onto
You are correct - the teeth are there for the headliner to get stretched onto. It is like the last place the headliner gets attached to when installing. The insulation takes up the open space and is there as a sound deadener. I used the aftermarket aluminized matting and covered every open space I could get at.
