Sorry for not phrasing and/or reading precise enough:
Do you assume/know that Mk. 11 without full antimagnetic shielding have seen actual military service and if so as Mk. 11 6B/346 or only downgradedas watch, wrist, general service?
I could imagine that watches downgraded to General Service were equipped with Hamilton dials: The Hamilton dial is cheaper. And the Hamilton dial would indicate "Hey, this is no navigitional wristwatch 6B/346, but a downgraded one".
Regards
Th. Koenig