Cool! How are you doing the 10W3? custom box?
Originally, I was looking at 2 10W6's and the JL 1000/1 for both but decided to tone it down. My last car had a MTX system with around 1800W pushing 2, 7500's. It was super loud...
When you run the power, I recommend you remove the windshield wiper plastic assembly near the battery. There is a bundle of wires that go through the firewall. Just use a hanger with the power wire taped to it and push it through. Make sure to seal it with some silicone...
You will need to take the lower passenger side trim off to get to it. Then just follow the nice tray that Infiniti designed the car to have that runs all the way to the trunk. You may need mechanical fingers to run between the front/rear door area and into the trunk. Run the remote turn-on with the power.
For the RCA, I'd run it from the deck to the driver's side and use the tray on that side of the car.
The ground is another easy one, use the seat belt mounting bolt for the back seat, which can be easily removed btw.
Good luck!! Here's some pics of my install: