Interesting. I'm not sure exactly what type of survey marker you saw; there are a couple of possibilities.
There is a section corner over by Miller, the SE corner of Section 16, Township 4 South, Range 3 East, San Bernardino Baseline & Meridian, but that's down off the ridge a ways in very steep country. Maybe you saw that, but it would be hard to get to. Another marker that the surveyors use is not a full section corner but
quarter section corner marker. If you were to divide up a standard mile square survey section into four equal square lots, the quarters would have a quarter section corner a 1/2 mile from the full section corner. In this case, a quarter corner would be very close to Miller Saddle. That could be what you saw, but I'm not sure. The survey section lines on a USGS topo are not exact. They are not an official survey plat; they're an approximation. It's possible that the full section corner is more accessible than one might think based on the topo map. I'll have to look around next time I'm there.
For future fun, there's a section corner that's fairly easy to find -- I saw it from a distance -- in the flatish area ENE of Joyce Peak, SW of Jean Peak. It's a stack of rocks with carvings in the trees around it. This is the SW corner of section 21, T4S, R3E, SBBM, where it meets sections 20, 29, and 28. One mile north of there, SW of
Little Folly Peak (between Folly Peak and San Jacinto Peak) are two section corners. I say two because there's an off set where they had to "fudge" the section lines for whatever reason. The fudge is only about 200 feet, but they would normally have two section corner monuments in such a case.
Fascinating what you might find out there. One never knows.
HJ

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