The 8 speed hub has a different spline pattern and the sprockets were, if memory serves, 1.9 mm thick compared to 1.7 mm for 9 speed. I'm not sure how you'd tell the difference between the spline pattern unless you had one to compare it against.
@andyp started
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The 8 speed hub has a different spline pattern and the sprockets were, if memory serves, 1.9 mm thick compared to 1.7 mm for 9 speed. I'm not sure how you'd tell the difference between the spline pattern unless you had one to compare it against.