I own a 2013 nissan versa SL that has the navigation/back up camera touch screen radio in it. I am planning to install a 12" subwoofer in the trunk to add some bass to my system. The question I have is if this head unit has the RCA ports in the back or not. I really want to keep the factory head unit because it already has everything I want in it. Has anyone else attempted to do this and if so do you have any pointers for me. I also plan on replacing the stock speakers in the door. Thanks for your help in advance, this is my first post since joining.