well, basically you build your TARDIS, preferably inside the bedroom(yes, you can build through the bedroom) and then use commands to link the position of the entrance to the vehicle, so that when you click the vehicle it teleports you there, then event a door with player > TARDIS_Exit and then event levers for other things. It's a build, not a freebuild cause you only build TARDISes.
aka my TARDIS mod development server