[Anonymous]

http://www.royalaeroclubtrust.org/raec-collection

Royal Aero Club collection has some material on Grahame-White built DH6s,though you will have to ask them if they have any drawings.

My experience of de Havilland designs – extending to Rapides & Vampires – suggests that DH didn’t like designing something twice so the fittings for the DH6 are probably common to other AMC/DH types.

https://www.crossandcockade.com/Uploads/CCI_1-38index-1.pdf lists other DH6 references, including one to the Canadian-built aircraft