Looking at old topo maps, there was a 4WD road that passed about 2 miles east of Heitz. It led to a an old prospect less than a mile west of Pincushion Peak. I think you could drive pretty close if not to that cabin. When it was incorporated into the Ansel Adams Wilderness in 1984, they blocked the roads. The first part of the jeep trail is now Onion Spring OHV but ends about 6 miles from Edison.
Like Lars said, not much rock back there but I bet there aren't many people either.