My brother Pat and I started from the Hurricane Creek trailhead, proceeded up Hurricane Creek trail to the Thorp Creek Trail which branches left from the HC trail at about 3 miles and crosses Hurricane Creek.. Note that the Thorp Creek trail is difficult to find ... a GPS point entered before departure will be helpful. I have 45.2864N 117.3061W for the junction, but that point is evidently a bit west of the actual junction.
Thorp Creek trail was in good condition considering it is not maintained. There are quite a few blow downs which must be negotiated. Also note that the Thorp Creek trail is not shown on the USFS wilderness area map, but it is shown on the USGS Chief Joseph Mtn quadrangle map.
There is an obvious large meadow with a steep pass at it's head in the upper reaches of Thorp Creek. We camped in this meadow (elev 7,450) and the decision proved sound as the next cirque around the corner (west) is scree-filled and exposed to rockfall.
The next morning we proceeded to the base of the aforementioned scree-filled cirque and headed up the eastern ridge of Sacajawea Peak. The route is a steep "walk up". We gained the summit ridge and traversed west over to the summit. Time up from camp was about 3 hours.
We started the ridge traverse over to the Matterhorn, but thundercloud development caused us to turn around. There was lightning and rain before we got back to camp.