so i have an 01 gtp, with the bose system. and i was wondering a few things. first, i want to install a pioneer premier FH-P800BT, how would i go about retaining the hud and SW options, second, would i be able to retain the speakers and stock amp? and thrid, what kind of box would work best in our cars, 12" sub. what area inside the box and what size amp? thanks!!! im just a noobie to the w-body bt thanks again!![]()