the box i want to make is shown on ddaudio.com as their chevy reg cab truck box. but i dont know how to come up with the cut sheet. where do i begin with the measuremtns based off my truck? dd doesn't have a cut sheet for their design or even measurements. so i kind of dont know where to start. i have built several boxes for myself and friends, but none of those have been as intricate as this one. can anyone point me in the right direction? thanks!