I figured I'd come back and let everyone know of my experiences with this as most people seem to be confused as I was myself. I used the Rockford Fosgate balanced line driver and spliced that into the pre amp signal, above the brake pedal, the harness coming from the headunit, I too thought it was confusing with the shielding and such but after messing around under there for awhile I've finally got everything how I think it should be installed. I can't remember the coding exactly for the wires I used but as you can see in the picture I tapped into the light pink and light blue wires, for the pre amp signal. Set the gain appropriately...
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