Here is one option. This is what I did with my 12"ers
The green towel on the floor is to hide the wires from the amp that powers the door speakers. ( I had not yet loomed them) That amp is mounted under the rear passenger seat.
The midgate is made of wood and has all the hardware from the stock gate. The box on the back is too large to fit through the midgate door, so the midgate does not fold all the way down. But it does lock and unlock just like stock. And yes, I did loose my window storage space. And I lost 9 inches of bed space.
One with the seats up.
Those 2 little 8" neons light up the entire rear of the cab at night My kida love them.
My 5 year old told me that the new speakers "Rattle" his bones