I've got a Mazdaspeed6 and I'm considering upgrading to a CX-5. I run the stock Bose head unit but have replaced the amps and speakers with high end aftermarket equipment. I use a digital processor to fine tune the audio. How difficult would it be to connect all this equipment to the CX-5 sound system without changing the head unit? Does the Bose system use an external amp that I can tap into instead of using high-level speaker outputs?