Hi Ian, you sound like an experienced British bike man, but there are some BSA perculiaries and you will find lots of advice on this forum, also like to hear and see your progress. I remember Nottingham in the 70,s as I used to visit some factories there, and remember the "fog" of material in the air from the lace and cloth industries, which I suppose like most British Industry has all gone now.
All the best Goldy