Upgrade the BLACK and ORANGE (ORANGE from CAR typically pairs with a YELLOW wire to the HU). Choose a smaller guage, like 16. It will be more than sufficient, as I selected that size from a length vs. amperage chart (4x23 Watts RMS, 4x50 peak).
I was able to get both of these wires through a rubber boot on the driver'* side. I ran the ground wire to a ground lug on the left side of the car, under the hood, by the washer fluid. It'* easiest to tap power directly from your battery at a common bolt in the maxifuse area. You'll have to remove that black maxifuse cover. You can't miss the bolt, it'* smack in the middle of the works.