>the Ministry of Transport required 10ft seperation between pairs of running lines
I was wondering how to get the 10ft in a simple way, so I measured the difference between the Streamline 6ft spacing and the Setrack spacing on the Peco way gauge. Guess what? The difference = 16mm which at 4mm to the foot = 4 feet, so the Setrack spacing is 10ft - sorted.
If the designer of the gauge is reading this, I bet he/she is feeling really smug right now!