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There may be a little information missing from original manual, in that the cam timing specified is listed as "at 1mm lift" in later publication. It also gives figures for 0 lift in later manual, but those raw cam degrees look nothing like the ones you've stated.Hopefully that may give you more to go on.
I've a first iteration 1969 manual, also a last 1978 in which the two sets of information come from, Honda genuine manual.No mention I can immediately find of where to measure (camshaft are often given timing criteria at a specific lift though as matter of routine) I'm guessing that the original just omitted this detail. The later manual gives timing for both, and so can be compared directly as follows;- intake opens @1mm lift 5 BTDC & 56 BTDC @ at 0mm lift. Quite a difference and likely to be causing your initial puzzlement. It follows all the others with dual readings too to check either way (beginning of cam ramp and @1mm) and looks distinctly odd at those numbers if you compare to "normal cam protocol.