Follow TucsonJim's route for sure.
Have been to both Zion and Bryce a few times; Bryce more than Zion. The best part of Zion is the drive in on Hwy 9. Check tunnel restrictions. I have driven the Hwy 9 with the tow vehicle and have gone thru the tunnel with that. I did not want the hassle of the rv restrictions. If you are over 50 feet they will turn you around and not let you thru.
Years ago johnna told me about the 89A and 389/ 59 route out of Fredonia and I highly recommend that.
Zion you drive the canyon and look up - other than the drive in and out. Pretty but hard on the neck. Some hiking.
Bryce you are up high and look down and it is spectacular - and great hiking if you can / have time. We like Bryce far more that Zion. But it will be cooler.
We are full hookup people so recommend :
Kanab - RV Corral
Lake Powell - Wahweap Campground
Springdale (for Zion) - Zion Canyon (avoid Zion River or whatever in Virgin - very pretty but ethics issues, high priced and attitude)
Bryce - Ruby's Inn
Provo - Lakeside
Kaysville (north Salt Lake City) - Cherry Hill
Be safe.
Lauren
Barbara-DW 55 years
Sadie-"Aussie" Terrier
06 Mobile Suites 32TK3
06 Chev 3500 4x4 Dmax
20 yrs PT RVing - 190 RV parks; some many times