Find the RV parks you want to stay at, and make your reservations NOW! I had to make a trip to Kalispell in August to attend a funeral. The only spot I could find was in a relatively new RV park on the Hwy 93 bypass South of town. $120 per night! There were several empty spaces there; why was obvious! I posted a review in the campgrounds forum here.
I know how hard it is to plan that far ahead, especially when you are unfamiliar with the area you will be traveling through. However, it seems these days it is almost a necessity.
Without knowing the highways you will be traveling, it is difficult to say what you might like to stop and look at. There are museums almost every where that are worth visiting. Deer Lodge is one such place, Missoula is another, Billings is worthy of mention, Kalispell is another, as well as Polson.
Cody, WY has a great museum, if you are interested in guns or Buffalo Bill or Western art. The Homesteader Museum in Powell, WY is great, too.
Idaho Falls has one of the largest Military Surplus stores in the country. I could spend hours in there wandering around and looking! In fact, I have done so!
Again, plan ahead, and good luck.
CM1, USN (RET)
2017 Jayco TT
Daily Driver: '14 Subaru Outback
1998 Dodge QC LWB, Cummins, 5 speed, 4X2
2 Kawasaki Brute Force 750 ATVs.
Pride Raptor 3 wheeled off-road capable mobility scooter
"When seconds count, help is only minutes away!"