I sent you an email scott. here is what i have to work with about 63" X 42" 22". I understand how to build a regular box but the midgate part is a little tricky. Do I first build the box. Then take out hte midgate and lay it down over a piece of wood and trace around it, cut that out, and then cut the holes out for the subs and then screw that piece of wood to the box once it is in place??? Thanks