Not sure is I ever posted this but you can get an MK3 proportioning valve, set it at a fixed height with a metal bracket and use it as a replacement for the NLA MK1 and MK2 proportioning valves. On the late MK2 and Mk3 the prop valve was mounted on the axle beam and would auto adjust based on the car's load with a spring that went from the prop valve to the car's body.. WIth a fixed proportioning height the valve could be mounted just about anywhere.