So this took me literally 30 minutes lol. The switch is temporary as it's all I had laying around the garage. I plan on getting a flush toggle like your photo.
Pull 4 tabs on lower trunk latch trim and unplug 12 volt adapter. Pull the three pins holding driver's side trunk liner in. Cut the brown/white wire and connect two wires to run into the cabin. Tuck them under the liner going towards the rear of the back seat.
The rear cushion pulls straight up and has two tabs under each seat. Shine a light so you can see a place to run your wires from the trunk.
Run wires under the seat and tuck up drivers side door sill trim all the way to the front. Pull side dash panel starting front closest to you (hinges at the back).
Unscrew two torx (T25 I believe) holding in storage container and pull gently outwards.
1/4 drill bit and switch installed
Can't even tell it's there
(Flat toggle will be even better)
