hi i am new to the car system thing, i love loud music and love the bang the gives you...my last system was stolen from me while my car waz parked at a club payed 3000 for the whole system and just 600 of it waz to have it installed. don't go that kinda money anymore so i am on the path to installing my own system... am trying to fallow this diagram i got but does not help much. 
i read that the power wire got to go opposite side of the RCA and remote so that it don't interfere . Wat am lost with is how to connect two amps to the same power wire, and connecting my mids and high. do i run wires to all the doors of the car or do i use exciting factory wires and how, i got a 2000 acura 3.2 tl with a flip out LCD head unit jensen wm9311ts two kickers 15" L7 a 3000 watt performance teknique
the power wire is an 4 awg 20 feet kickier wire, ok so i got the head unit Harness and the one for the car, i braid the two Harness together and then run 4 sets of speaker wires from the amp to the head and barid them in with the wires from the speakers. i say run 4 set back to the head because it 4 + and 4- that i will need for each speaker of the car ?
The stock cable should be fine. Obviously you'd get better performance if you rewired it with premium cable but that's a lot more work than simply extending the current set.
you are on the right track. when you connect the two harnesses, just cap off the speaker output from the HU, and then connect your new speaker wire runs to the CAR SIDE speaker wires in the new harness.
Just connect all of the wires and then from the back you can determine which speaker is which by popping it with a battery or connecting it to the amp, or with a test tone generator
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