Jack - if your son may be stationed there another marina opportunity arises. The Navy base at Apra Harbor has a very sheltered marina open to those who are authorized patrons of US military facilities. Most typhoons hit the island from the east, and this marina is on the sheltered west side of the island.
Facilities are acceptable - I know one family from Hawaii who lived aboard at this marina for the duration of the father's tour. Has a large area for dry storage and DIY work, but no travel-lift so you'd have to hire a crane locally. Best of all is the marina bar atop the office building that overlooks the basin & entrance channel.
Another option is that way up into the harbor, past the commercial piers (again Apra Harbor) is a well-protected area among the mangroves. Used to be a rather derelict liveaboard area last time I was through there, but it provides good shelter.
Here's a link that shows Apra Harbor... the Naval Station marina is the smaller basin between the inner harbor area and the ship at anchor in the outer harbor. The patch of light blue water...
http://www.guam.navy.mil/navalbaseguam.htm
The commercial port lies off to the right (north) of this picture.
I miss the place... diving visibility in the outer harbor was 80ft on a BAD day, the WWII underwater national park is there... many shipwrecks to explore and an incredible wall dive 40 yards off the beach.
Hope you and/or your son get a chance to see the island in person!
