Norris:
Just so you know, all camping in the San Gorgonio Wilderness is by permit only at designated camp sites. Trail Flats, High Creek, and Fish Creek Saddle are the highest trail camps en route to the summit. Camping above that is off limits, unless you want to camp on the summit itself, which is permitted. Camping is not permitted at Mineshaft Saddle.
Fish Creek is the easist (in my opinion) route to the top. If you could take a three day weekend, you could do something like this:
Day 1: Fish Creek Trailhead to Fish Creek Saddle.
Day 2: Fish Creek Saddle to summit and return to Fish Creek Saddle.
Day 3: Fish Creek Saddle to Fish Creek Trailhead
If you only have a regular, two day weekend, you'd have to go all the way back to the trailhead on day 2 which would make for a hard day.
For Fish Creek Saddle, there is water available at Lodgepole. There is also water available this time of year at the last creek crossing before the big switchbacks that go up to Fish Creek Saddle. See point "C" on the map link below. You can either go up to the saddle and set up camp and then hike down to Lodgepole for water or fill up at the aforementioned creek crossing and carry it up, depending on your preference.
There is water at Mineshaft Flat trailcamp. Mineshaft Flat is a couple of miles down a side trail from Mineshaft Saddle, and the water source is another third of a mile down the side trail from that. You'd have over a five mile side trip to get water at Mineshaft Flat. I don't think it would be worth it.
There is a reasonable short cut you can take to the top. Take a look at
this topgraphic map of the area. You'll probably want to scroll around a bit and zoom in and out.
A = The Fish Creek Trailhead.
B = A creek crossing with highly reliable water
C = The last creek crossing before the switch backs. Fill up here.
D = Fish Creek Saddle
E = Lodgepole Springs (Alternative fill up point)
F = Mineshaft Saddle (no camping)
G = the top of the switchbacks on the Sky High Trail
H = The major SE ridge of San Gorgonio Mtn
I = The summit of San Gorgonio Mtn
The short cut is basically this: When you get to the top of the switchbacks on the Sky High Trail and start to cross the major SE ridge of San Gorgonio Mtn, turn right and follow the
steep but doable ridge from point "G" to point "H" to point "I" (the summit). It is cross country (no trail), but you can see worn spots that indicate that others have done it. It's fairly simple navigation; just stay on the top of the ridge and keep going uphill. If you start going down hill, you're off route. This will cut out at least a mile, maybe more, from your round trip from Fish Creek Saddle and back. The ridge is defiitely harder than the trail. You'd have to decide based on your knowledge of the parties involved whether a shorter more difficult route (but doable) is better than an easier, longer route.
Hope that helps,
HJ