Summary - Peterson Ridge is a relatively easy bushwhack and an unremarkable summit, without a view or open space. The pleasant hike in on Service Trail 35 includes a modest climb and is mostly under the trees. There are trees for antennas, ATT cell service was five bars, and two way APRS messaging worked. I had no luck on 2M, even with a yagi. The drive can be done in a passenger vehicle and there is plenty of parking at the trailhead. One caution: This is a busy part of the forest and this trail is frequently used by motorbikers.
Long Version - USFS maps show FS115 as the access road to Peterson. 115 has been converted to a multi-use trail called Service Trail 35 and appears to loop around the ridge to connect to another old FS road, though I didn't follow it past the summit access point. Google maps will route you to the trailhead, which is easily reached in a passenger vehicle. There are many much-visited campgrounds here and a fair amount of road traffic.
I hiked approximately 1.2 miles along 35, climbing 300 feet, and then headed SW back toward the summit, staying north of the two lower high points. This route climbs another 200' over half a mile and isn't a bad bushwhack until final summit climb. Coming back down, I hiked north, pretty much straight down the fall line, to the trail, which save half a mile and mostly easy hiking but for the last hundred yards of gnarly tangled brush, trees, and deadfall.
The summit itself is small, brush and tree covered, and without a view of any sort. There are plenty of trees and, in September at least, flies. I didn't make any 2M contacts, spotted myself over ATT cellular and APRS, and didn't take a single photograph. After an hour or so on HF, I packed up and headed down the hill. On the way out, I encountered a group of motorbikers tearing up the trail.
While not a destination peak, this is one of those bushwhack summits you can do in a couple of hours, especially if there are other SOTA ops on local peaks, so that 2M is easy. The hike is pleasant, the bushwhack