On 28 February 1965, the ammunition ship arrived at the Lockheed Shipbuilding and Construction Company yards, Seattle, Washington. There having reverted to in commission in Reserve status, "Mauna Kea" commenced FAST (Fast Automatic Shuttle Transfer System) conversion. Completion of this conversion, which would enable her to transfer a missile from her hold to the magazine of a missile‑firing ship in 90 seconds and allow her greater versatility in servicing the fleet with the addition of a helipad for vertical replenishment capabilities, was delayed for 8 months, because of strikes and lack of necessary parts, until June 1966. Then followed a fitting out period and intensive post-conversion shakedown exercises, which continued into the fall. By November she was again an active unit of the Pacific Fleet’s Service Force and on 28 December she departed her home port of Concord, California, for her ninth WestPac deployment.