We've been working on a FABCO modified truck, hope to have some completed pictures next week.
http://www.tresburrosgarage.com/Capay-History.html
Neil Wilson is the guy you want to talk to, he knows more about AA's than just about anybody, he is responsible for the AA Truck club and its website. Site link below, lots of good data, great guys to talk to.
http://aafords.com/
and AA forum
http://forums.aa-fords.com/
You should also Join Fred Carlton's AA page on facebook, lots of interesting stories and pictures.
If you want to know where there truck was made, you may be able to find it on Steve Plucker's page. I noticed he posted above but was to humble to post a link to his production research page, so I'll give it to you.
http://www.plucks329s.org/
Again, that's a great find.