It has been a long time since that entire road was traveled, however, I've been on portions of it lately. Leaving Ridgway headed west on 145, you will encounter a few miles of fairly steep grade as you depart Ridgway until you pass by the left turn to Telluride. Take your time and enjoy. A drop off will be on your right, but it doesn't last long. Once up on "top" of the mesa, it's reasonably flat as you head over toward 141, then turn to 491. There are still a few twisty parts, but nothing I'd consider a huge obstacle.
Lizardhead Pass is in good condition, and well maintained. Telluride is beautiful, and you'll end up in Durango after Lizardhead Pass, then on to Cortez and pass by Mesa Verde - definitely worth a stop. That road is reasonably wide, and I'd have no reluctance driving it in our 37' DP. There are lots of campgrounds along the way with big rigs present.
If you REALLY want to skip the mountains but in general use this route, consider heading north out of Ridgway on 550, then turn left onto 141 north of Delta/south of Grand Junction. That whole section is fairly flat, and has beautiful country as you pass through Gateway - worth a stop. The guy who started The Learning Channel and Discovery Channel owns a beautiful resort there, with a fantastic automobile collection. Worth seeing if you like cars.
Take a look st Google Earth - you can "drive it" and see what you think before actually heading down the highway.
Either way, you can't go wrong. Hope that helps! Enjoy the trip!
Joe and Debbie, Emma the Aussie Cattle Dog who adopted us
2012 Discovery 36J, Blue Ox and Air Force One, 2010 GMC Acadia Toad
USAF (Ret) WDØM http://wd0m.com