We left the Brainerd Lake trail at the dip near Willow Lake - where the trail turns west, we went east up a boulder slope (staying left of all the streams). This short steep ramp leads to a wonderful shelf, shown as the easternmost fork of the stream. The footing here is superb, the mosquitos not too bad, and the scenery is amazing.
The good news is that you don't have to hop morraine all the way to Southfork Pass... there are still deep snowbanks in good condition leading up the eastern approach. With a over a week of consistent rain the wildflowers are really in good form!
Southfork Pass is unbelievably bad right now. A bergschrund is opening up, the bridge is shaky, and above that there is hard water ice with lots of dirt in it. Axes bounce off, crampons don't sink, and spontaneous rockfall threatens to knock you off the slope (one climber was hit by a small chip while the big ones flew by). Oh, and if that's not enough, there is up to 6 inches of mud/rock on TOP OF the hard ice in places, meaning you have to kick steps through muck into concrete because the muck moves when you just step in it. Didn't pause to measure the angle, but it's steep enough that we used a static rap line (25 meters will do, 50 if you want to pull it down after you) on the way down (all except Ramaker the Magnificent, who cleaned the route). The north side is all snow/ice, the south side is bare.
The bad news is that my supposed alternate route up Disappointment doesn't go (the topo maps are wrong and luck is not smiling), so we did Balcony instead. Well, those that didn't turn back at Southfork and those that didn't get disappointed about Disappointment, anyway. That left Jim and I.
We camped at a stream feeding the high lakes on south side of Southfork Pass, at 12.2k - well protected from the wind that buffeted the lakes, and out of the way of lightning strikes from evening (5 hour) tropical storms.
There is an analog cell phone signal if you walk far enough west to see the Pacific Crest Trail heading south to Mather Pass!