You have a couple of options here. For one, I wouldn't run the comp system off of the deck because the rule of thumb when building sound systems, is that too LITTLE power is often more harm than too MUCH. What amps are you using? I know that Rockford makes a nice multi channel amp that could probably power the entire system adequately. I believe it is the 500ix, but I could be wrong. You could power your fronts and rears off of 2 channels and the subs from a third, since you can run them in mono. Good luck.
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Jeremy
1993 atx 122k miles
-PIAA headlamp bulbs (thanks Fratperformance)
-fish tanks installed
-fog lamp mod w/ blazer fog lamps
-6" 5% tint border on windshield
-black body filled lettering
-wclewis "powered by yamaha" badges
-Sho Shop Cold Air Induction Kit
-Lund blackouts front and back
-cincysho colgan half bra with "SHO" lettering
-KVR chrome cadmium plated rotors with carbon fiber pads
-Sho Shop cat back system with magnaflow chrome tips
-Performance Plus y-pipe
-TX personalized plates "SHO FUN"
-Shoshop underdrive pulleys
-Shoshop 80mm MAF
-60k completed by Sdpatt
-Redline atx tranny fluid and water wetter
-Ted Breaux LPM
-D4U1 computer upgrade
-Rebuilt 94/95 AXOD tranny with TRANS-GO shift kit