Wanted to have fast charging available (wired and wireless) for my phone, which requires access to a 12V source. Added a 12V outlet under the phone dock and also behind the passenger footwell panel (for my dashcam).
I came in here to post this video, because it's very helpful! Big thanks if you are the one who made it @jonco223 !
This is typical week 1 activity for every car I buy, especially with lack of sockets by Tesla. In fact I just spent this morning reversing this on my mini getting it ready to trade in for my 3 very soon!
The one question I have, is if the 12v socket harness runs up to another accessible location further forward, possibly less trim to remove.
Yes, my video. Good question - I looked for the 12V outlet wiring behind the panel in the passenger footwell, but it doesn't run that way. It appears to run under the driver's seat and along the driver's door edge and then up under the dash. Also looked in that area for a 12V constant source, but only found a 12V source that drops to 9V when the car goes to sleep...
I ran 12V similar to you a couple of weeks ago, but didn't get past getting the 12V wires into the console bucket. My next job was going to be taking it all apart again to find out where I could mount a 12V outlet; your excellent measurements will make that a lot easier.