Would an early North Carolina keep 14-inch guns?

Would the earlier North Carolina-class battleships use quadruple 14-inch turrets?

No; Japanese 16-inch ships would drive the United States directly to a 16-inch main battery.

The United States would design against the heaviest weapons its treaty rivals were authorized to field. Once Japan chooses 16-inch guns, an American 14-inch battery no longer offers the desired answer. The early North Carolina lineage would therefore carry 16-inch weapons. Britain remains the exception that might choose 15-inch guns because the saved weight can buy speed and protection while supporting upgrades across its older battle fleet. Gun caliber follows adversary requirements rather than an isolated technical preference.