Does anyone have any great input on what size and deminsions I should use for this Alpine Typx X 12" . I have a guy supposed to building me one with the Alpine specs. Is that a good idea to make that sub perform at it's best? Or should I go with something else? It going in the back of a SUV. The length cannot be any longer than 38" long, The height and width there are no limits. I am hearing the recommended spec sizes from Alpine does'nt make that great of a SQ box. Does anyone know if that is true? And if so what do you pros recommend. Any advice would me appreciated. Thanks you for the help.