Bobby,
I would love to get a copy of Brown Bros and DH AGS parts info, will send PM

AGS 972 and AGS 500 from the WW2 period, and a Concession Note from DAP (Australia) relating to substitution of AGS 972 for AGS 500 have been digitized courtesy of ANAM Moorabbin Archives and will be loaded ‘by Christmas’ on the Standards page of silverbiplanes.com From these datasets you can navigate to SBAC equivalents.

There is also another DAP chart dealing with substitution of AGS screws and fasteners with more commonly understood British Standard equivalents, as well as more British Standard ‘A’ standards from the the late 20’s through to WW2.

Ed