I am building a custom Subwoofer box for my car and have all the parts except the mdf to make the box, I am unsure what size it and the port should be for it to sound how it should. The drivers I have are X2 15" Pyle PLPW15D's. The area in the car I have to work with are: Width - 35" Height - 16" Top depth - 12" Bottom depth - 20" I have 2 depth's because I would like the back of the subwoofer to be angled against the backs of the rear seats to use up all available space, like a wedge shape on the back of the box. First of all I want to know if the measurements I have would be a good size for these drivers if not the height and depths can be adjusted slightly, secondly how big will the port have to be? Thanks for any help. James.