There is a lot of parking available. Definitely could fit a fifth wheel RV in there so truck should be fine. There is no pull through parking, though, so you'd have to park "across" a bunch of normal spots. This is not a busy park (200k visitors total per year).
I don't think they allow commercial vehicle parking. There is a large overflow lot for Class A RVs and I saw short class C's in the main parking lot
Thanks! Your answer is awaiting moderation.