Alright, if you have components in front, they would have 3 parts, a midbass driver (6"), a tweeter, and a passive cross over ( a little box with electronic parts inside). The 6" midbass normally gets mounted in the door's oem location. The tweeter (high frequencies like symbols, triangle etc...) typically gets mounted in the side mirror pod(sail panel), or dash corners, or higher on the doors. The cross overs can be mounted almost anywhere, as it just splits the signal between the two drivers ( midbass gets lower frequencies, tweeter gets higher ones). From your list of equipment, you do not have components, you have co-axial speakers. This means the tweeter is attached to the midbass and both are mounted in the same location (not necessarily a bad thing, but you can't move the tweeter). I'm not sure why your old dash speaker is still playing, as it should be disconnected and/or removed. The rear speakers should be attenuated (reduced output) either by giving them less power (seems like you're restricted in that regard as you're using the deck to power them equally), or by restricting the signal going to them by fading to the front more. This will allow the fronts to be the primary sound source, and allow the rear speakers to "fill" in ambiance and additional information(again in a typical system set up). The subwoofer should be adjusted to blend in with the speakers, so as not to over power them (if your deck has a sub output, then you can adjust this as well). If properly set up, the system should produce loud volume, clean, clear sound, and sound should eminate from in front of you or with extra processing power (depends on your deck or equipment) from around the rear view mirror area, with bass sounds more central. Anyway, I hope that gives you a better idea of what you have and what you should ask for at the shop.

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2004 300M SPECIAL
Alpine CDA 9833
Alpine Pxa-h701
Alpine Rux-c701
Rockford fosgate p400-4
Rockford fosgate p4004
Hifonics BX 1205D
JBL c608 GTi
JBL p963
Infinity 2.5" center channel
Alpine type R 12"(2)
all active SQL set up with 2000 watts rms