Relocated the existing stereo head to underside of matrix, dropping it far back and down enough to maintain existing vent outlet.
One photo shows left side placed on right to double check fit, and you can see grooves cut for bottom and below stereo panels.
Used some leftover 6mm/1/4" Okume veneer marine ply I had leftover, applied some ebony stain and a couple coats of marine varnish.
Tapped into reverse light circuit to steal ign. sworched power run through 5 amp in line fuse to power double cigarettelighters, one for GPS and one for either light shown or dual USB adapter.
My IPhone 10 fits in there as well.