teofft
112
another hint
The first Cosmograph Daytona was reference 6238 and is sometimes referred to as the pre-Daytona Cosmograph. Rolex retrofitted some of these references with a Daytona dial and bezel (mine has a 1.4m serial). Apparently it was not unusual for these early models to have "mismatched" casebacks. So mine is not a 6238. The movment as you can see is the Rolex 722 movement based on a Valjoux 72 movement. It still has nearly the entire 42 hour power reserve and of course sports a classic column wheel design. I've narrowed it down for you... Any more guesses? and please keep the pictures coming!