Details
Start from the McClellan Butte trailhead lot. Find the trail on the southwest corner by the signboard
Follow the meandering way to reach a power line right-of-way in 0.2 miles. Pass across, and on the other side follow right, along a very old converted rail grade. (Or an alternate is to continue up the hill a short distance to join the Iron Goat road-trail and follow it west.) At 0.6 miles, cross over Alice Creek, where artificial water works create a lot of splashing below. Keep left, following an upgrade to reach the Iron Goat trail at 0.7 miles. Go straight across. The trail works its way southwest with Alice Creek on the left, and at 1.2 miles swings northward to cross forest road 9020-1.
Continuing more steeply uphill on a brief northward turn, the trail soon reaches the irregular top of a rib, a relatively pleasant area, snaking in a generally southwest direction with comfortable elevation gain. Soon all of that turns into hard core switchbacks; you must grind out almost half of the total elevation gain here.
At about 2.8 miles, the straight-up strategy breaks down, and the trail begins cutting across the steep east-facing slopes. There is still elevation to gain. At about 3.2 miles, there is another brief switchback exercise, then back to the theme of cutting across slopes, with the summit on your right, and views to Alice Creek valley deep on your left. At 4.4 miles, pass the south end of the butte, following a distinct bend to the right. (It is possible to follow the watershed boundary down along the rounded top of the ridge, across to the Alice Lakes from here, but there isn't much to recommend this beyond sheer isolation. Keep out of the watershed area, which is closed.) Now swinging to a northwest heading, climb a bit more, then drop back about the same amount to reach a narrow bench that parallels the ragged ridge on a northeast heading. This spot is a major snow trap and can remain sloppy wet into late July. Otherwise, things stay pretty tame along this final 0.9 miles. Just before approaching the summit, there is a cut back to the right going steeply up to a comfortable rocky saddle.
If you are not intimidated by the prospect of bouncing a few hundred feet down the severe, highly-exposed rocky slope on the east side, the knife edge of the ridge to the summit promontory is the right kind of short scramble for you. Sturdy boots, good balance, and steady nerves are a must.