This will be your end result.

This is the only visible wire.

Use the long installation wire that comes with your radar detector. Start by pulling out the interior over the pillar which is shown above. Just pull it out a bit enough to push the wire in. Route the wire over to the weather sealing by the door and push it under that all the way down to the passenger foot well.
Remove the cover over the power harness by the right passenger foot area. There is a plastic upholstry nut that you can unscrew and pull off with your fingers. Also remove the panel under the glove box. It pulls off very easily. Now pull off the door seal plastic and the other one that encloses the right side of the dash. You do not need any tools to remove any of these interior panels. You can just use your hands and do it all within 5 minutes without any risk of damage.
Now look at the power harness on the BCM (body control module). We are going for the orange wire #3 in the diagram. It is the P/W power supply (RAP) at battery voltage when the ignition switch is ON, as referenced on page 54 of http://www.nicoclub.com/FSM/EX/2008/INL.pdf .

It's the one here that can be seen stripped. I put a pink zip tie to hold all the wires in place. Please use a fuse on your radar detector. One should come with it.

Here is what you see on top of the visor.

And here's the final product.

Here is the gallery http://imgur.com/a/Vz4R4
