Daniel,
These peaks are in different jurisdictions, so the rules vary. Here’s an overview:
Mt Wilson – There is overnight camping in several designated campgrounds en route to Mt Wilson, and campfires are typically allowed in the established fire rings. There is no overnight camping at the summit. There is quite often water flowing in the creeks here most of the year.
Cucamonga Peak – You can camp overnight and permits are self-issue at the trailhead, but no campfires at any time. There are no established campsites at the summit, but people routinely do so (I did that when my wife and I hiked Cucamonga this summer). No water once you leave the creek in Icehouse Canyon.
Mt Baldy (Mt. San Antonio) – You can camp overnight but no campfires and no established campsites. No water above the Sierra Club Ski Hut.
San Bernardino Peak – Limber Pines is one of the established area where you can camp, en route to the summit. There is a seasonal spring nearby.
San Jacinto – You cannot camp at the summit (and not really any good spots), but here are established campgrounds at Little Round Valley (on the Marion Mountain Trail) or in Round Valley (from the tram). There is sometimes water at both of those places, but this year in particular Round Valley dried up during the summer. Campfires are sometimes allowed — check with the ranger station in Idyllwild when you get your permit.
San Gorgonio – There are no established campsites at the summit, but I know that people have camped there. There is no water and no campfires (no wood, for that matter) at the summit. However, there is both water and campfires (conditions permitting) at the established campsites en route at Vivian Creek, Halfway Camp and High Creek.
There are no rules about hiking the Six-Pack of Peaks as day hikes, or even from a particular route. But there are no shortcuts to accomplishment.
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