I assume you'll be entering Zion from I-15, Hwy 9. Where are you staying?
If you are staying at the Springdale entrance and were planning on leaving Zion via Hwy 9 east you'd have to disconnect your toad and drive both vehicles through the tunnels to get to Hwy 89 and up to Bryce. Check out the tunnel information on the Zion Nat'l Park web site for details.
An alternative to include Glen Canyon/Page, AZ area at this point would be: from Springdale/Zion entrance, backtrack on Hwy 9 west to Hurricane, UT. Then pick up 59 south toward Colorado City and it will then become 389 in Arizona taking you to Fredonia, AZ. Then get on Hwy 89 and follow it into Page, AZ. There's a very nice RV park right on the water and Antelope Canyon tours can be had from this area. You could also do the 'dam' tour or a boat ride on the lake.
Then go back on 89 to Kanab, UT and north on 89 to Bryce, etc.
If you take the tour of Monument Valley I would skip Valley of the Gods (you probably wouldn't want to do it in your vehicle) and just do a 'drive to' Goosenecks SP for a quick picture. There's really no reason to spend the night there.
I don't see a good route to fit everything in without some backtracking.
In my opinion you could also skip Four Corners. There's nothing there but a desolate area, some trinket sellers and a plaque and also an admission fee. Besides, it's really in the wrong place if you read up on it. :)
Have a great trip!
