u/Brew-Tang-Clan

I’m relatively new to in car audio so forgive the basic question. I have a fiberglass enclosure that is carpeted over. I ended up having to get a spacer for the sub as the magnet hits one of the grooves inside.

My question is how should I mount the spacer to the box? The easiest way seems to be to screw it down but would it keep a seal against the carpet? Should I trim the carpet and glue it down or am I overthinking this?