I have downloaded a little over 20 pages of book 14, the pdf file is not available yet, and am a bit worried if this will reveal any new motorcycle registration numbers. I didn't see any in the pages I downloaded. Just trucks trailers jeeps.
There are now 16 ledgers from the Australian War Memorial available for download. These contain details on thousands of vehicles - the focus for this group being mainly the BSA's, Nortons, Royal Enfields, Indians ect but it has all sorts of military vehicles. I have spent hours looking through these and now now have the original Australian Army rego numbers for all 5 of the frames I have but there is much more to be found - the shipping details for a batch of Nortons to Singapore recently discussed is one brilliant example.