I have traveled most of that route over the course of a seven day trip a few years ago. At that time it was very beautiful scenery and easily passable for a stockish R-50 Pathfinder. Post last years "epic" fire season the western portions could be interesting.
I would like to attend but I do not have compatible GPS at this time, I use my Nuvi with backroads map books to navigate.
If I can find a compatible GPS,that is a viable replacement for an ancient Etrex I use for APRS this is on my list, but so far no joy at a reasonable price.