I am wanting to get some more bass and sound out of my current setup. I am very new at this so looking at some steps and info to help me. I am wanting to keep in on the cheaper side, but know I might have to sacrifice some money. I currently have a Z71 ext cab, Bose radio, XM, steering wheel controls. No onstar. I plan on keeping the stock radio, just looking at adding some extra speakers, subs, amp, whatever, to help me get more thump. Where should I start?