Leave the bike at home. Easiest approach to Goat Flats/Three Fingers is now the climbers' path from S Fk canyon creek. The gully road washout is only a mile before the S Fk canyon creek bridge crossing. Cross the bridge, look for tank-trapped old road on your right, take that road upstream about a mile, crossing one major stream/ravine outlet. Before the second (Sevenmile Creek), take the rib uphill in the woods. It's marked as a dotted line in "green Fred".
If you're OK with routefinding this is a very direct route to Goat Flats, almost as fast as the beaten-up Tupso Pass trail, and much pleasanter. It's half as long as the Tupso pass route and gains about 1400' more of elevation. If you've been avoiding the Three Fingers/Goat Flats area because of the mobs, this is the year to do it. Long may the washout remain unfixed!
It's apparent on a map that the closest road approach to Goat Flats is in fact the S Fk Canyon Creek crossing. The eight miles of road beyond that, to Tupso Pass, actually take you away from your destination.
The washout is easily negotiated by foot, incidentally. The washout is due to a stream blown out by debris flow from a seventies-era clear cut a few hundred yards uphill. A pleasing circularity there, a road constucted for logging plants the seeds of its own destruction.