You will have no problem with Hwy 50 to Grand Junction. It's a beautiful drive and many RVers do it.
The national parks all have campgrounds and Zion has one with electric. Have a good trip!
Full-Timed for 16 Years
.... Back in S&B Again
Traveled 8 yr in a 40' 2004 Newmar Dutch Star Motorhome
& 8 yr in a 33' Travel Supreme 5th Wheel