How does the speedometer gear stay in? MY bud took this apart and I cannot find a clip

My bet is on the oil seal old and warn out. There is probably a bit of a friction fit to the seal that holds the gear and shaft in place till it is installed, then the gear is captive.
There is no flare on the gasket surface as seen in the tracks on this old one so the only retention method would be the seal friction itself.
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