I have an escalade ext (07) and need help with an aftermarket sound system... I want a couple of 12s but am unfamiliar with sounds systems ... I know im probably going to need it installed in the bed with a custom box right? Can someone tell me what im going to need to make this happen?...i dont want to walk in to an audio store and get raped with the price because i seem like a dumbass...thanks alot for the help ... I truly appreciate anybodys help

There are more than a few boxes for ext. You can get one that hangs on the midgate , one that replaces the midgate , or an under the seat one .

O ok thanks, what about a box in the bed? Maybe a couple of 12s or 15s in the bed? Does anyone know if the sound is good?

I also have a questions on this.. are there boxes you buy were you can fit 2 12's into and have access to the back hatch as if the boxs weren't their incase you wanted to haul something and needed that extra room. Oh and I also wanted to add 5 new speakers instead of this bose system what would you recommend I do? replace the speaker wire and what speakers should I get and what amp should I hook the speakers too? I just want something louder and cleaner then what bose can offer.