Round hold off valve serviceable?
Hello, just starting to put my 68 back together. I am switching from front drums to front discs. While cleaning up some of the parts, I removed the large end nut from the "hold off valve" in order to clean and see if it was rusted or stuck. I have never had one of these apart and not sure how it works. Rubber disc looked ok but did not remove the rest of the valving inside. Can anyone shed some light on servicing this valve or is it usually not required?
Also, switched to a 69 disc setup (Rotors, calibers etc...). I am using a 69 master cylinder. I am hoping that the hold off valve and steel spliter block are the same on the 68's and 69's. There was no proportioning valve on the rear line on the frame when I bought the car.