Is a 40' RV too long for much of MX?

We have been roaming all over MX in a 40 footer for the past 7 winters. Yes, things can get tight. Read the Church book. Plan your route. We use Microsoft Streets & Trips 2013 to plan our route to make sure we do not find ourselves in the middle of small towns. We tow a Honda CR-V for the sight seeing trips. We have been to many places they say we cannot go with a 40' and have survived. How experienced are you with the size? Note that fuel in MX may not be OK for post 2006 diesel engines. Use Google Earth to look at campgrounds you might stay in. Have a GPS that does not rely on internet as you may not be able to get internet in many areas. Keep in mind that when planning you may not be able to go as fast or make as many miles as in the US - we do not ever drive at night in MX due to topes, cows, horses, etc. (Topes are called speed bumps in the US and are everywhere in MX and cannot be seen at night). If you cannot find a large enough campground when you look in the Church book you can ask here if anyone knows of a Pemex station or other place to stay - ask people to be specific with things like Latitude and Longitude as some directions given here can be next to useless. Many here have blogs in their signatures - read lots of blogs.