Yeah, yeah I know rear fill is evil but looking beyond that!
Has anyone done this? Because of the metal underneath the rear deck I can't do a flush mount.
I'm thinking about building two small cabinets for 6.5" coaxial speakers. Since there are those holes in the metal I'll screw through a piece of wood and the rear deck material into the bottom of the box. That way they can tighten the box down while also pulling the rear deck material so it won't rattle when the subwoofer hits.
Sounds kind of trashy but If the box is black and if I could pull it off properly it should look alright. The boxes wouldn't be big enough to obstruct the view of anything. Just big enough to house the speakers.