Depends. Are you using a S/X or 3/Y? WE have a project for adding USB hubs and ports and hiding them.
My friend is about to publish this project.
USB Port Extensions and Security | TeslaTap
on his website.
Maybe it will help you.
You have to hope that they person breaking into your Tesla is in a hurry for your stuff and expecting to see a flash drive and does not take the time to look for a cable running to an obscure location. Give me what they expect. Put a decoy flash drive where its easy to find.
I suggested take a M/F extension cable of short length. tie a knot or double the male end. Stick the male end under a panel piece of trim to secure the cable from being pulled out. Leave 3-4 inches loose near the car's existing regular USB ports, so it looks legit, as though the other end is connected to the car. Plug a decoy flash drive in to the female end. It doesn't have to be large capacity or even work. Its just to fool the bad guy. Now, leave it.
You can plug your SSD into the real USB port as what looks like just a power cable or something and hide the SSD. If you are going to use a flash drive or SD Media adapter, I would find another M/F extension cable for the real USB port, plug the male end in, and thread the cable away and maybe under carpet. Plug the media or flash drive in the female end.
Leaving a dummy/decoy flash drive within sight will serve your purpose and your bad guy will likely stop looking for more, when he finds the one you want him to find.
There's no guarantee. But the idea is to lessen your risk by making it easy for your bad guy to find something easy. And I hope all this is a waste of your time and your car is not broken into.