Hello Steven, You're lucky because the Norton ledgers have survived and will show date of despatch and to which dealer or agent. At this period, engine and frame numbers would have matched. Details of gearbox and fork numbers should also be shown, together, certainly for 1950, with the original tester's name.
There is generally more information about bikes originally sold in the UK as the initial purchaser's name and address were filled in, presumably upon guarantee registration. There is less info on bikes shipped overseas as the local importers were responsible for warranties.
The original ledgers are with the Vintage Motor Cycle Club (VMCC) in Burton and they will normally provide what information they can free of charge (Annice in the library is very friendly to deal with). They have a good website. The Norton Owners Club have microfilm copies but only provide free to members.
I recommend membership of both
Good Luck with your enquiries. Let us know how you get on.
Rich
