I don't think they care what kind of vehicle you sleep in, but you have to reserve the space, or at least pay for it, online. I'd you get there at the right time you can talk to the Ranger and they can answer all your questions. Thru score up every morning at around 6:45 and verify if all the campers on the sites are registered. They are the throughout the day at different times as well.
No Car Camping
Tent but car is ok I'm sure must pay online countyparks.gov/payment
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