Almost everything above the main deck changed, including the bridge, davits, troop spaces, weapons, magazines, and ammunition routes never required in civilian service. The drawings make clear why calling this an easy ferry conversion understates the naval-architecture work. The economic logic was nevertheless strong because a sound hull, propulsion machinery, and shafts preserved the most costly foundation. Those retained systems let the Navy redesign the rest of each ship around a new mission faster and more cheaply than starting with an empty slipway.
Notable Point · 16:40-19:19
Why a radical conversion could still beat a new build
Plans of the rebuilt ferries reveal new davits, magazines, guns, accommodation, and structure built around a reusable hull and machinery plant.