Off-the-shelf guns constrain a large combatant

Could the proposed large US combatant carry two modern twin 5-inch gun mounts instead of the single gun shown?

The hull could theoretically accept them, but the program's preference for off-the-shelf equipment makes development of a new twin mount unlikely.

The two twin mounts are accepted as theoretically possible on the proposed hull. The objection concerns developing the necessary gun installation. A preference for off-the-shelf systems makes that new development unlikely in the assessment.