Afriend and former resident of Wyoming told me that I-80 was called the Snow-Chi-Min Trail back in the 60s. (You older guys will get this.) Weather will dictate your travels there.
One App I love is RVParky. Their website is here:
www.rvparky.com
Great site for finding RV Parks and trip planning.
Here's a screen shot of a trip we made in 2017 from Seattle to Boston area.
Murff