Specifically looking for info on the issue around 70 Carbs # with date codes stamped L9 or M9 and additional M with the 71 manual choke installed vice automatic thermostatic choke for hemi cars.

Did mopar offer replacement 70 carbs with manual choke as over the counter? These carbs have the 70 numbers but supposedly 71 cars came with them. Yet at the same time Carter is making 70 carbs for 70 cars. So why are 70 date coded carbs being used modified for 71 production which won't start for another 7 to 8 months. Why not just use the Nov/Dec 69 dated carbs for late 70 cars. Use the later date Mar70 carbs and beyond for early 71 cars if necessary. Seems way out of sync for carter, though some say things were hectic at carter by 70. Just curious if any firsthand knowledge on this issue from either an older Carter tech or Mopar guy with direct experience. Hard to believe Mopar used 70 part number carbs on 71 hemis all while having carter building 71 carbs for the 71 cars too. Thanks.