Car Stereo Installation

you can use MDF or metal/aluminum, what every is easier for you to work with. just keep in mind what would be easier to do a finish panel for. my opinion would be to use 1/4" and 1/2" MDF with metal brackets then you make a trim panel to finish it off if your wanting to save some box space. if having space is of no concern then you can make a solid panel across the box (be sure you leave room that the door will close).