I ended up getting the consolve vault for my model3 for 1/2 off. Install was not difficult with my smallest socket wrench and an extension. It's the most secure method that is readily available I could find for handgun storage. It might not be CA legal due to no fully enclosing the gun, but the things that are legal are far less secure. The trunk is probably the least secure place on a model 3 to store a handgun, and of course that is what CA would have us do since there are no room under the seats in my 3. Sounds like the Y might have more options.
Just need a tight fitting lockable soft case to put the gun in before putting it into the vault to make it "compliant"...