Then there is a group of years where parts books were printed that contained so many mistakes that they were reprinted. In some manner, or way, the dicarder books found thier way into local salvage houses (MCE comes to mind) that specialized in buying production scrap. Has anyone that is reading this been in MCE's celler? Selling rejected parts, and scrap to local motorcycle trade was a small side occupation for a few factory workers. A lot of these parts that failed inspection, and the odd rejected parts books found their way in to the market only to make the whole what-fits-what, and what is new-old-stock a whole different problem.
This is one good thread.. Yes I have been a few times in MCE's celler or basement in the 1980's. it was good experience to haggle with Sid and I still have some parts NOS BSA parts that I bought from him. I must have been lucky cause they fit.