Are there any ways to visually check which synchros are in the box, assuming that it has been stripped down? I remember reading in the Digest a long time ago something about a circumferential groove in the ring, but my mind may be playing tricks on me (again
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Which is the superior version? And if an early box was to be converted to the later synchros, are there any other bearing etc surfaces which would be incompatible with EP oil?
And I'm not even going to attempt to ask what the differences between Spirax and Dentax oils are!