The mod is now finished, everything is set up and all works well. Here are a few photos of the final results with the control box for the radar detector, laser jammer, and parking dynamics electromagnetic front parking sensors.
The latter works great -- stopped me 3" from the 6" curb in my parking space -- I'd never gotten that close as I was always way too cautious without the sensors. As I have a radar gun and laser gun tester, I was able to double check the functioning of both, which is excellent. Remember, all of this is mounted in the nose cone, which makes it very accessible and easy to mount. Haven't been able to test the EZPass yet but will soon.
Once I clear the hole in the firewall I used a flexible rod (the orange thing in the photos) to pull all of the cable through. I did one connection at a time and worked very carefully. Once all the cables were pulled through, most of them were way too long, so I trimmed off all the access and put new connectors on the ends. The power is from the glovebox light fuse in fuse box #2 and I made the ground connection to a bolt in the frunk. As I didn't want to take anything else apart in the passenger compartment I ran the leads for power and ground through the hole. Here are a few photos of work in progress.
This photo shows where the cables come through firewall hole just below the lower back of the touchscreen. This space is easily accessed once the side panels for the center console have been pried off (easy to do as they're attached with spring clips). If you look carefully you can see the hose in the background (a gray shape curving up). The hose diameter by the way is about .8" This space is also great for packing in any excess cable.
Here are all the loose cable waiting to be attached to the control box.
One of the most difficult parts of these steps was getting the cubby with all the hardware in it to snap back into place. It's just a case of getting the two rear spring clips attached first, and since they're hard to see and the angle is a bit tricky, it took about a dozen attempts before it snapped into place. The photo below shows it just before I snapped the right side fully into place.
If anyone has questions about this mod and any of the steps, post here or PM me.