Funny you should mention the Alcatraz tommygun, Judy. We held our 40th reunion last week and many stories were shared about its arrival on the island.
Check out this photo from 1975, right after it was transferred to GOGA from SFPD:
http://www.pbase.com/jamartini/image/153193071/large(Note the careful handling we gave the artifact. Everything in accordance with NPS Museum Handbook.)