There should be both the nut that needed to be turned around and a spacer.
To get to a diagram, go to www.westernhonda.com, click on online parts then OEM parts fiche, then motorcycle parts, then enter year (only 1974 for 350F, for some reason not '73, the year of my bike, but it's all the same), then front wheel. it's #4 in the diagram.
And pay no mind to XB, he's proving himself to be a troll with limited or diminished capabilities.