Raptormann11

Hey guys, I'm a new member and I know this has been brought up a million times but none have answer my questions to the extent that I need them to be. Allright, so I have an 05 Chevy Silverado ext. cab WITH (Blowz)Bose audio -_- I am going to replace the stock head unit with a Pioneer AVH-P4400BH and was going to use the Axxess ASWC harness and the metra (GMOS-04 GM)one to keep the chimes and the steering controls but my main question is can I bypass the amp all together? I want to replace all the door speakers, and put 6x9's and a single 10" JL W3 subwoofer in a box under the rear seat. I thought I would keep the Bose system and just replace the speakers and match the ohm rating (which no one can agree on) then just do my pre-outs from my head unit to hook up my sub and other set of speakers with externals amps. Will my idea work or will the sound be crappy? I want to retain all the factory sounds and functions with the steering controls but i would rather amp the door speakers with a external amp and just unhook the Bose amp and subwoofer.

Thanks a bunch