Looking at Dan Checkoway's numbers (seems pretty close to the mark)
Empennage - 200 hours
Wings - 400 hours
Fuselage - 420 hours
Finish kit - 166 hours
Wiring, Panel, FWF - 390 hours
Cowls, Baffles etc - 130 hours
Wrap-up - 320 hours
And that's for a standard build.
So 10% seems a reasonable guess, but they're all different