Sounds like you already know the ins and outs of this....we ran across one road, Chief Joseph Highway (from outside Cooke City, MT to Cody, WY) is not recommended for over 40', however our truck & trailer were 42', but because it's not one unit (articulated), it could make the turns fine.
Grades are one thing (and they are quite a bit near Gardiner/Mammoth - as well as Dunraven Pass, Sylvan Pass and Beartooth Pass), but the hairpin turns are another. Once you camp your trailer, then you can take these other passes (Dunrave, Sylvan inside the part and Beartooth outside), which are all scenic drives and worth the effort.
The Tower Junction to Tower Falls road is a mess - Mon-Thu is a pilot car with 30+ minute wait, on Fri-Sun two-way, but very rocky and hard - the reward - lots of black bears in the area!
We just left, and was a great year for bears - have fun!
We'd rather be out traveling, but I still work so we're part-timers.
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