I was looking at a lot of this stuff off the original hand drawn CR prints vs the new CAD ones. They don't jive with each other from page to page never mind rev to rev. The thing that made me laugh was your comment on the cut lengths as a lot of them seem to be made to economic material cut sizes. I believe the frame rails were 8 footers and a lot of other stuff is 6", 2', 3' etc.
I agree and think Al is onto something there. Hey Al what are you shortening your track, flange dimensions to? Check out the metric mad numbers on the thread about it.