The route from the East from Rockhouse Basin is a challenging and fun route to the summit. It requires good route finding skills, a ford of the South Fork of the Kern, and a long and enjoyable class 3 scramble to the Fin. The total distance is about 11 miles, one way. You must descend into a valley, then climb back up to reach the Fin.
Finding the right place to park can be tricky, especially at night. The climber.org description
of how to get there is pretty accurate. However, the road continues North past the trailhead and is NOT closed as indicated on the page. You can drive to the PCT on the road. They aren't kidding when they say you may need a GPS to find the trailhead, as the steel gate is almost impossible to see at night coming from the South, though in daylight you have a better chance of seeing it. The road gradually becomes unsuitable for low clearance vehicles after the trailhead, so if you encounter questionable terrain, you've gone too far.
From the parking area, head down the old 4WD road for 2.5 miles until you reach a cattle gate. Shortly after the gate, you'll want to go cross country and leave the trail to the North, possibly following the dry creek bed. The trail as indicated on topo maps is intermittent and difficult to follow. However, cross-country hiking is quite easy in the desert terrain. After about 3 miles, you will want to cross the Kern. We found the easiest place to cross was just at the south end of a large rock formation at a bend in the Kern just South of where the main trail crosses the river on the maps. In mid-November the water was never more than a foot deep here.
Nice campsites can be found throughout this area. Trout Creek will likely have water, but don't depend on Tibbets Creek having water for your summit attempt(it was dry in November). See the image of Rockhouse Basin at the bottom of the page for exact locations of the campsite and the best place to cross the Kern.
Head cross-country up the ridge. There are hints of a trail here and there. Pick your spot to start going up the class 3 rocks. Earlier turnoffs will result in slightly easier climbing, but a few more ups and downs. Climbing the gully just to the South of the Fin is more direct, but the boulders are huge and will likely take more time to traverse.
You meet the main route at the North side of the summit ridge.