I talked to the director of the San Diego Auto Museum http://www.sdautomuseum.org/ in Balboa Park, and he took the position about 18 months ago. The AMX-3 wasn't in the museum's collection then or since. Damn. Love that design. He thinks it may be at the Peterson Auto Museum http://www.petersen.org/ in Pomona.
http://justacarguy.blogspot.com/2006/11/beautiful-amx-3.html#links
The website for the Peterson Museum is especially nice, trust a guy who spends lots of time in front of the laptop, and you can browse through most of the cars on display in a slideshow style. Worth it! I was looking there to learn about it for this entry and just realized how much time I'd spent looking and reading. http://www.petersen.org/default.cfm?DocID=1008&cat=The%20Bruce%20Meyer%20Hot%20Rod%20Gallery&ID=350&index=1