It's much easier to get up to Perry Aiken Flat from Leidy Canyon. The way is pretty clearly marked on the topo. With a 4x4 you can drive pretty far up. In fact I took my old Fork Maverick as far as an old rockslide that's only about ten minutes' walk below the 4x4 trailhead.
A short distance above the 4x4 trailhead follow the ramp-like jeep road to the left. It brings you to an open cowpasture with a corral with two gates. A good trail up to Perry Aiken Flat leaves from the uphill/smaller gate. This trail switchbacks up onto the ridge, then follows the whaleback ridge with moderate grades.
Near the upper treeline for Bristlecone Pines you can traverse left into the north branch of the north fork of Perry Aiken Creek, which is a cirque on the north side of White Mountain Peak at this elevation. There was ample water in this cirque when I was there in early summer. It's a great place to camp and explore, as well as a base for dayhikes up to White Mountain Peak via the dividing ridge between this cirque and the main north fork to the south. You can also backtrack to the whaleback ridge and follow it up to peak 13,9xx which is separated from WMP by a difficult knife-edge ridge.
How high is high? Also, how high is that cirque
I didn't have an altimeter along, but trying to recreate it with online maps I'd say you can drive up to 8,000' at about 37.702N, 118.221W. http://www.digital-topo-maps.com/ makes it look like the jeep road goes all the way up to Perry Aiken Flats, but it's really just a foot-trail (or cow trail) above 8,000'.
If you sidehill over from Perry Aiken Flat, you'll hit the cirque at about 11,500'. You can stay pretty much on the cirque floor up to a low ridge at 12,400' separating this cirque from the much deeper cirque of the main North Fork. Above that the headwall goes up to about 13,600' before you're out on the cirque on more moderate slopes. When I was there in July the cirque floor was well watered. In fact it was boggy in places. It would make a great campsite and you could then explore the upper slopes of White Mountain Peak and Peak 13,980 at leisure.
All in all, a much easier route that going up Perry Aiken Creek but keep in mind that it gets you into the cirque of the Northwest Fork, not the much deeper North Fork, although you have excellent views down into it.