My guess is that a lot of the plans were on plain paper.
I was in the local push bike club, holding a Hill-Climb on the Horseshoe Pass. One of our members who worked at Broughton, said he could enlarge the Start-Sheet. I said it was to go on the wall of the event centre, so that everyone could see it....
When he brought it back from Broughton, it was the size of the wall... All on one sheet of paper, with each name about 2cm high.
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