Stereo install amateur (n00b) needing help. I searched online and tried to find some answers, but it's just a little overwhelming.
Car: 2004 330ci, Harman Kardon stereo
HU: Factory
Front/Rear: Polk Audio DB6501 6.5-Inch
Sub: JL 10wv3, JL box sealed box
Amps:Alpine Power Pack, xtant 121m...