Had time this afternoon so hardwired my Escort 360 Max to my Jaguar, took around 30 mins to do and not too hard.

Had the radar detector and hardwiring kit from my previous cars, so the radar is the older model. But you could probably do this with other radar detectors as long as you have the correct hard wiring kit.
Here's the link for Escort:
So depending on your car and model I would do some research and see which fuse is where. I had to do some trial and error on this part since I did not realize that the TPMS, 5V battery, and Heated/Cooled seats are on even when the car is on. I wanted a fuse or component in the car that when the car is off its not being used, since I only need the radar working when the car is on.

The best option for me was PF28 Steering Wheel Angle (its a 10 amp fuse) located in the passenger fuse box.

1. The passenger fuse box is really easy to access, its just on the left side next to the door and get a prying tool or just use a flat head to open it up.
2. The fuse cover has the labels on it, and I went to Jaguar.com manual to make sure that it was the right fuse
https://www.ownerinfo.jaguar.com/doc.../proc/G1815972
3. Pulled the fuse out, wrapped the wires onto the fuse and just plugged it back in.
4. I couldn't find a ground in the fuse box so I had to open up another panel located right next to the dash on the left side. See picture below, you could just open it up with a prying tool or flat head for this as well, comes off really easy.
5. I routed the wiring around the door seals and window seals to hide most of the wiring.

Basically the red line in the pictures is how I routed the wiring of the cable.

Hope it helps! It should work the same way for wiring a dashcam or anything you want to hardwire.