Most of the time since October has been spent sourcing small rubber parts: Caliper rebuid kits, brake hoses, brake master cylinder seals, clutch slave seal, etc. The last ones, the clutch master cylinder seals, arrived last week from the Netherlands, courtesy of a helpful Vintage Lamborghini Garage member (thanks Paul).
While I was searching and waiting for seals I dismantled and cleaned the brake safety switch (below) and the front/rear proportioning valve, and replaced all four brake hoses.
Brake Pressure Differential Warning Assembly (PDWA) switch
The parking brakes had never worked, so I took them apart to figure out how the system functions. Each rear disk has a dedicated parking brake caliper. To make a long discovery story short, they are now rebuilt and properly adjusted, problems overcome, and working well for the first time since Iíve owned the car!
Rebuilt parking brake caliper
The clutch and brake systems have finally been completely rebuilt.
Dec 6th: Today I bled the brake and clutch systems. The PDWA is leaking. Fortunately it's the same Girling unit found on a Triumph Spitfire and several other cars. Rebuild kits and o-rings are available for a few dollars. I ordered some from The O-Ring Store.
Dec 19th: The O-rings arrived this week, and they are too big. My fault. I've pulled the PDWA out of the car and removed the rings. I'll reorder the correct ones.
Dec 29: I've called several O-ring companies trying to find the correct rings. The square-cut rings have a 2mm cross-section and a 5.7mm ID. No one had these metrics square O-rings or spent much time listening to my story. Then I called Gobal O-Ring and Seal and talked to Freddy Gutierrez (extension 5578). I love it when someone will spend 46 minutes to understand my needs and get me the right part - even if it's just two o-rings. That's customer service! Freddy was great and is sending me a few possible replacements to try.