Hi Ravenhook, Pillboxes are my second passion. If any members are interested in British anti invasion defences then try the following link:
www.pillbox-study-group.org.uk
An excellent site, full of info and pictures.They also have a message forum so if you have any questions post on the site and you should get a reply.
You may also want to try the defence of Britain database:
ads.ahds.ac.uk/catalogue/collections/blurbs/324.cfm
The defence of Britain project has a large but not complete record of pillbox locations in the U.K.
Your first stop should be the pillboxes study group site. How many members know that we were still using 6 pdr 6cwt mkII as anti tank guns in pilloxes in 1940?
Quatermass