I am not sure what to think of this model anymore, I finally found the Diamond Edge crystal to fit this and it is named Excellency "D" along with reference numbers 1146E-2 and case number 2687. It measures 23.8 x 22.2 mm with curvature on both measurments. The GS part number is CMY308-33A
I will post some pictures of the crystal packet and the White Gold/Black Diamond dial (twin) that I have in the next couple of days.
The '66 BB catalog lists a CMY2386 with out the Diamond Edge as fitting a Senator 'I' (same spec's as the Diamond Edge) and the Engineer 'I' & "J" taking a CMY2299 with the same curvatures and measuring 22.9 x 21.9 mm. The Senator crystal just doesn't fit this watch.
Is it a Excellency "D" or a Senator? the Engineer crystal is too small and not a Diamond Edge style...