So far as I know Ralph, the magneto strap was black painted. The small diameter oil pipes were dipped in something or other to plate them. The easy solution (and one which nobody has yet suggested looks wrong on my bikes) is to paint them with silver Hammerite Smooth. You would get away with the same trick on the rocker box nuts - which you can hardly see once the tank is on anyway.
36 4G, 37 VH, 53 ex ISDT KHA (project), 54 KH(A), Healey 1000/4 (project)
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser.