Here endeth the saga of Kirkallanmuir Weighs signal box!
Well, er, not quite! I decided that it would be nice to have some lighting in the box, but wanted to keep it 'self contained'. I tried a couple of grain of wheat bulbs powered by a 1.5v button battery, but, while this gave a nice yellowy illumination, the battery died after a couple of minutes. Nigel Cliffe kindly sent me some LEDs and resistors and rigging a couple of them up with 3 batteries (the LEDs need 3.5v) works well, although the light is a bit on the blue side. i tried to correct this by painting some cling film yellow and covering them with that, but that just gave a rather insipid green colour. I replaced this with a more orange colour which is better, but still a bit green. More experiments required, methinks!