Just back from Simon W, an early 6139-6000 from July ‘69. Notched case, 2-part chrono sweep, but no CRC. Whether the crystal had already been changed before I received it, or whether this one was already too late in production for the chrome-rimmed version I’m not sure. The crystal has been replaced (again?) with a Ben Levy special. I have put one of the aftermarket JDM bracelets on the watch - discussion on that to follow in another thread….