A couple of thing to note about the GoPro's. Our nav unit USB ports do not produce enough power to maintain the GoPro from the specs I found. The usb port on our nav units is to transfer files.
If you try to use it to power up your GoPro you will soon learn that the GoPro will die when the battery runs out.
The nav unit max output is 500mA or less.
The GoPro needs approx. 1 amp to both run and maintain the charge.
I use the plug in power port (looks like a cigarette lighter port) located inside the consul. Then run a usb cable from there out on the passenger side there is a small cut out thing to allow a cable to pass through without getting squished.
Ran it out and strait down, then under the consul, up to the dash, followed a route underneath the glove box and then up the pass. A pillar and along the windshield trim to the rear view mirror area.
I have a mount behind my rearview. Note to turn OFF your red LED's or they will bounce off the windshield.
It was set up this way for use as an In Car Camera.
This power port is always on and will charge your GoPro even with the key off and the camera off.
Of course if all your wanting to do is to charge it in the vehicle and then use it outside you can always just plug it into the power port and then throw it in the consul.
In order to be able to plug the cable in to the camera without drilling or cutting into my waterproof housing I purchased a Skeletonized housing from GoPro. This allows you to leave the housing on and still hook up the cable as well as remove and insert Micro SD cards. I wanted to save my waterproof housing for scuba diving.