Side walls help

Good evening everyone! Awesome site and great info out there! I've started my build today basically cutting sections of plywood into correct size before sealing and carpeting however I've ran into an issue......I'm mounting 2 stereo speakers and my switch panel along with the stereo head unit on the side walls but can't seem to come up with a design I like that will work and give me the allotted space for clearance.....basically want a carpeted "box" symmetrical on either side of the boat between back and middle bench, an extent ensign inwards of the side walls. Here's a picture looking into the area any advice would be great!

You're putting a system in a boat?

No I'm not putting a system in the boat it's a marine stereo with 4 speakers I just need ideas on bringing out the side walls enough to mount 2 marine speakers and one marine stereo head unit I need the depth behind the walls (sides) as these systems sit flush with all components behind it I want it to look clean but having trouble with my design IE see picture below except want on side walls of boat