Ok I have have 2013 challenger with the BA 6 speaker setup with factory amp. I already had the stereo swapped out with the pionneer avh-x8500bhs. Plus I got the PAC adapter so it works with my setup and keep steering wheel controls. Now I want to upgrade my speakers. Not sure if I should change out all 6 or just door and rear. Plus will add a new 4ch amp. Can someone recommend a good setup of speakers and amp?I will be having a shop install it.