I wouldn't see why not. The scenic road is a large one way road. Wide enough for two cars even though it is one lane.
Yes. I would even feel safe navigating it with a semi
Yes. But you will need a reservation for entry. Just make sure you safely park and take a hike!
Scenic road yes 100% Be more difficult in some of the smaller parking lots if they are full.
I'm not familiar with RV, but I can see RVs up to 24 ft, but I haven't seen 36 ft passing through Red canyon area yet. It is safe to say that you can drive through because the road is standard 2 way, plenty of places that you can park and have fun, but you will not be able to make a u turn, except in a very few places towards Blue diamond area, especially on the weekend when the road traffic is very busy similar to california roads, but that should not worry you because the road is about 5 miles stretch or little longer and connected to hwy's on both ends,
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