I saw a thread on this site or another that explained the things that you need to do in order to put subs on a Bose system, or replacing the headunit and keeping bose speakers. Anyways my question is can someone point me in that direction cause I can't find it.

 

this is for the head unit . but if you have the money for a headunit and subs, i'd definately go ahead and get some speakers too. by the way, try the audio forum.