I’m looking into purchasing a 105.012 66 with the CB case. The seller’s watch looks great, as the facets unique to the CB are prominent, the bezel is a winner, the hands are correct, etc. My only pause is that the dial has the narrow “T Swiss T” spacing. Spacefruit’s excellent resource, Speedmaster 101, notes that a 105.012 66 should have “closed spaced Swiss Made T’s, some wide spaced Ts”. I’ve looked at as many pictures as I could find and I would say 85-90% of the CBs I’ve come across include the wide “T Swiss T” spacing, not the narrow. Still, I did find a few examples with the narrow spacing. The Speedmaster101 description is used to cover both the HF and the CB case so it’s unclear if there is or should be consistency among the CB dials. Anybody have any insight to offer? Here are a couple of links to what I consider extremely nice CB examples, one with narrow and one with wide. Narrow: https://omegaforums.net/threads/105-012-66-sold-on-ebay-for-£5100-7700.21624/ Wide (thanks to MSNWatch): https://omegaforums.net/threads/just-aquired-105-012-66-case.13293/
I can only theorize because I don't know. Narrow T's are earlier than wider. I observe narrow T's on earlier watches, so far not on confirmed later 105.012's. I know that watches from traders are often far more extensively worked on than they care to admit. If I had to put money on it, I would bet a narrow spaced T dial only left the factory on earlier 105.012's, but I cannot be sure.
According to MWO both close and spaced T's are correct for a 105.012-66 (their B2 and B3 type dials). My late ref CB -66 (#2544xxxx) has the close spaced B2 type, so I'm not sure if if there is a close/early - spaced/late rule. Interestingly, MWO also says that on a 105.012 the close T (B2) dial is rare & the spaced T (B3) dial is more common. That doesn't distinguish between the HF & CB cases though, so if people are observing a lot of close T dials on CB cases then maybe it's possible that more of the close T dials found their way to CB cases.
It looks like the different models were often in production concurrently, despite the -66 etc year designations used.