Peter, interesting photo of your park brake setup. I also have a similar setup, but I notice you have solid tubes between the valve and where the tubes go through the firewall (that is the vertical pipes, I notice yours is an A so doesn't go through the firewall at that point ). I originally had solid tubes there as well but was concerned that if the tubes were not exactly the same length, then strain on 1 pipe could cause a fracture at the flare. Also vibration of the firewall could result in the same thing. I changed to flexible hoses in that area. Maybe I am being over cautious, what does everybody think?