Lassen Area Campground recommendation

We stayed in a little rv park in Mineral just outside the south entrance to the park. Great setting but the park was not cared for - trash cans full, restrooms and showers very dirty. I don't know if your rig would fit, but you could give them a call. I think it was called Mineral Lodge and RV Park. We have stayed at Manzanita a few years back and drove through it this trip. I did not see any big rigs. Thank you for your service.