Hi Rick
I would have liked to help you but you are about 15 years too late. I was given, by the widow of the chap who fixed and fitted all the Met Police's speedos from the 50's onwards, all the spares and Smith's books that he had squirrelled away over the years. Unfortunately for you I gave them to a friend who dabbled in clocks and speedos, I know I should have kept them but space is always limited.
I do know that he designed and built the test equipment that they used, including the calibration rollers for testing the cars and bikes, but there was no Smith's testing equipment in his garage when I cleared it.
Before you ask, I think all the stuff I gave away ended up somewhere in Australia.
Ned