Ingraham rates this as 3rd, but holy cow, either the mountain has changed a lot since his day (doubtful), I'm a wimp (possible), or ratings in his day were very different than now (likely). From the end of the approach (just east of the peak, see below), ascend a gully towards the saddle between Lost Peak and The Wedge. You have two choices, take a left leading ledge, around an exposed corner then trend back right to the ridge and follow the ridge to the summit. You will find a short low 4th class pitch (low 5th?) and a short exposed knife edge to cross then easy terrain to the summit. Alternatively continue up the gully until you find a short 4th (low 5th?) class pitch to the summit (I didn't go this route, so someone might correct me).
The normal route can be approached from the west (Modoc) or east (Aguirre Springs). We approached from the east, and I found it easier and shorter than the west approaches. From the west, either climb to the Lost Peak/Wedge saddle and traverse slightly east to the summit pitch, or climb to the Organ ridge just south of The Wedge, then descend the gully to the east to and turn left into the gully leading to the saddle between The Wedge and Lost Peak. Climb either route described above. From the east, take the Pine Tree Trail to it's halfway point (or take "secret trail" to this same place...don't know secret trail? Well, it's a secret). From the halfway point in the Pine Tree Trail, ascend a ridge/welt immediately above the primitive campsite. When practical, traverse into the gully to the right (north) of this ridge (before the gully splits). Ascend the right hand gully through a fairly thick (but passable) maple/oak forest (nice color in the fall). Ideally you'll exit this gully left at a small headwall, if you miss the exit, you wind up at the saddle between Third Peak and Lost Peak (you'll know you're in the wrong place if you have to ascend a chimney to get under a large chockstone). After the left turn, the terrain leads back into another gully that ultimately will culminate at the saddle south of The Wedge. You don't want to go that far, you want to turn right into another gully over a short stretch of rock, where some class 4 scrambling leads to the routes described above.
None required, but you'll likely want to rap from the summit back down into the gully for descent. A number of rap anchors can be found sprinkled around the S. and E. ends of the summit. I believe the ones to the south are destined to drop you back towards the west approaches, rather than the east.
Panoramic view looking south from the summit.
Fall foliage during approach from the east. Like ...