Guess you tried all the spots in CA. One of my favorite spots in CA was at the top of Alamo mountain. Up the grape vine and off hungary valley road then west. Need to call the ranger station to make sure south gate is open. I've had a 10 1/2 ft camper up there. Don't know about 5ver. Other favorite spot is north of Cody and west. Out 120 then west over dead indian pass. When the road makes a hard right to go over huge bridge before Crandall you go straight on the gravel. Follow to the end. You will be in Sunlight basin. You will see a few TTs out there. All locals. No water except creek. Pit toilets. The camp ground is not marked. You would need a forest service map. A few other camp grounds along the way that are marked.