I am building my railings using 3/32 inch music wire and 3/32 inch ABS angles. The stanchions are 4 scale feet, but 3.5 scale feet from the top of the catwalk. The 3rd rail uses the same technique as shown in my second generation 3rd rail in my subway with the exception of the flat head screw. Instead I cut the same material used for the catwalk as the 3rd rail chair. I have yet to install the protection boards.