I think that's the best route. We took it through Guad from Patzcuaro in April last year for the first time and it was fairly easy. If you come in on the highway from Mexico City & Morelia get on the lateral when you see trucks doing it (this is the only part you will be required to be in the lateral). Not too far in, you'll see signs for Chapala for which you have to get back in the right of the 2 main lanes (merge to your left before the overpass), go under the overpass and exit right - you'll end up south-bound heading for Chapala. The south and north-bound lanes separate for a ways and come back together in time for the exit (right) for Periferico, Tepic & Colima. Carry on for several miles, ignore the Colima exit and the road gradually turns north. Follow the signs for Tepic and you'll do another right exit after the overpass which will have you west-bound and you're done. It helps if you look at the route on Google Earth and you can go to the ground-level view for details on the places to turn - make sure your navigator sees it too, I might add !- hope this helps - RYV