Hi
I have seen some photos of Pannier Tanks pulling coal trains in the the South Wales area which have 'Dinner Plate' size white discs mounted on the front or rear of some engines, these discs also have numbers and letters on them - see below.
These engines also have Lamps mounted in the relevent Headcode positions, so can someone explain what these discs are and what the letters and number mean, or refer to please?
Thanks, Dave.