I have a 2011 GT with the 500 shaker system. Sounds great works great but has me wanting more. I have decided this needs a sub or subs in the trunk. I will probably do that then upgrade the speakers. Can I do this without changing the deck? Also what have you used that works or doesn't work. I looked at the couple ones on crutch field but not getting exactly what I want with information. Can/will you help me out? Pictures also if you have them!!!