well the subs are Kenwood kfc-xw1200f's, the box is 15 inches high i believe, whatever the height from the sheet metal on that shelf in the back area of the cab, to that rolled out area is, 4.5 inch top width, and 6.5 bottom width. the bottom could be 7, but unlike the new seat it would hit the plastic hinge covers. its made of 1/2inch MDF. the width is of no concern because I'm pretty sure ill be able to fit 2 subs between my 6x9 cabinets, unless their like 28 inches wide
. the box is 54 inches wide now, just so you know. i wont build a box that goes higher than that rolled out section, or lower than the flat area back there, and i wont alter the cab in any way. il check on that heighth measurement asap. i appreciate the response!