Swedish cars had those round tax things back in the 1960's fastened inside the car. Left lower corner of the windscreen.
We had left hand traffic back then, everybody drove on the wrong side of the road.

Changed to right side 1967. One day at a certain time.
I remember the scary moments.
Most cars had the steering wheel on left side so passing slower big trucks was a nightmare. My father asked my mother if it is ok to step on the pedal and pass. Slow going Ford Taunus 12M Super 1960.