Ive recently rebuilt the distribution block and metering valve in my '69 with new seals for the metering valve and valve rebuild kit from Muscle Car Research. The distribution block and metering valve have been soda blasted and appear to be in great condition, the issue I am having is when the brakes are applied brake fluid is leaking from the rear of the metering valve where the "shaft" slides in/out. Im still getting lots of fluid at all four wheels when brakes are bled. I have 3 '69 metering valves that have been rebuilt with the parts from Muscle Car Research and all 3 leak. I have got rid of all the old dot 3 and are using dot 5 now which Scott from Muscle Car Research says is compatible with dot 5. I haven't figured out what is causing the brake fluid to leak from the metering valve in the rear, any help would be greatly appreciated.