correct carb dates for a 67 GT350???

trying to determine the correct date range for my 67 GT350. The car was scheduled for 2/22/67 actually completed 3/8/67 from Ford. Completed at Shelby on 4/18/67. My motor has dates of mid January so one school of thought is that the carb should be dated in this range. It was my understanding that the intake and carb were replaced and put on at Shelby American so the carb could be dated anywhere from the build date at Ford (3/8/67)to the completion date at Shelby American of (4/18/67).

If any of you guys with date correct cars could chime in on this I would appreciate it.
Also looking for a balancer,front cover and distributor dated January 1967

Thanks for the help.