Hi my question is, on a 1975 US TR6 can you remove a brake PDWA valve piston on the car. My PDWA valve is leaking through the switch so I need to stop this. My options. 1: do nothing other than cap the switch with a 3/8 UNF bolt and copper washer, my worry about doing this, if one side of the piston rubbers fail completely would this stop the equal pressure keeping the piston central and possible only having either the front or rear brake circuit working, I do not know the travel