I think you don't understand how the switch can work if there is no place to put the lever in the middle of a street. The answer is simple: you only put the socket and every driver brings his own lever. This system is still used today when the electric drive malfunctions. [Here's a video ][1]where it can be seen how it's done. We can see the driver putting the lever in dedicated socket. [1]: https://www.youtube.com/watch?v=3LzGIyB50TU&t=3m40s