Give me a few days to close mine out to ensure no more snags and I'll give a full foolproof writeup on everything. I've done a full skar build utilizing all factory locations. But, additional items are required to make everything work well.
Radio - Kenwood DDX9704S
Amp - Alpine 5 Ch. PDX-v9
Front Dash Speakers - JL Audio C2-350x
Front Door Speakers - CDT-Audio ES-6iM
Rear Door Speakers - JL Audio - C2-600x
Subwoofer OEM Enclosure - 86150-76010
Trunk side panel with subwoofer grill - 64740-76020-C2
Trunk floor board next to subwoofer - 58418-76021-C1
Trunk Cargo Liner (w/ subwoofer cutout) - PT208-76111-25
Subwoofer - JL Audio - 10" 8W3V3-4
Steering Wheel Control Adapter - PAC - SWI-CP2
I swore I had JL Audio front door speakers....but I wrote down CDT Audio. Well, either way, that's what I have!
The trunk looks 100% OEM. You wouldn't even know an aftermarket sub was installed. The AMP is under the driver seat. The radio, is exactly where the OEM radio would be . The sub puts out plenty of power. Very happy with the system.