Hi Peter ,

diligent, very good, thank you.

From 1st Ex 2446C GMT there are 2 dials,
one with short 20/40/60 markers at the running second , like the screw back GMT, 110/111xxx
and one with long markers like the following executions, both small sub register 112xxx-
fonts on sub dials (2) (thickness) differs and marker at 3/6/9/12 sd differs and "T" nearer/far to pivot too,.
the early bezels have 18 teeth, later 12 (17/11) per partition.....
in short, different dials... may be change of manufacturer.

cheers
Mich