Yay! We made it. We drove down to Belize in a 2005 Jeep packed to the gills with things for us and the dog. That actually turned out to be a good thing. The central route was great although we have nothing to compare it with.
We crossed the border into Mexico near Laredo, TX at the Columbia Solidarity crossing at 8:30am. Nobody else was trying to cross the entire half hour we were there. Since we were the only ones there, they did make a half-hearted attempt to inspect our Jeep but it was so full they gave up. It wasn't that clear to us what place to go in what order but we worked it out and got underway on Hwy 2 over to 85D. About 30 miles in we got stopped at a genuine inspection station and they looked at our papers briefly and waved us along. "These aren't the droids we're looking for" is what came to mind. They were way more interested in trucks. Sticking with toll roads we went on to Monterrey and down to St. Luis Petosi where we stayed the night. Totally easy day though the sign for some of the exits was sometimes confusing to follow. Garmin to the rescue! It took awhile to adjust to all the truck traffic and Mexican rules of the road but not hard.
Our 2nd day was the opposite kind of day. First let me say, we should have known better than to plan the Arco Norte leg of our trip around Mexico City on a Friday. Less than 2 hours down the road from St. Luis Petosi, traffic came to a complete standstill and there was no way to get off and detour. We sat there around 2 1/2 hours before moving 1 km and sitting another half hour. That was not a good time for this drive. Lots of stop and go traffic slowed us down further and Puebla road construction topped it off. We made it to our hotel in Veracruz just before midnight. We didn't mean to drive at night and didn't again. Thankfully, we'd planned 3 nights in Veracruz and were happy to be out of the car for awhile.
The drive out of Veracruz wasn't bad despite the Monday morning traffic. We had no problems on the way to Villahermosa. Nice stay there after a fairly short driving day. Villahermosa to Chetumal was a mixed bag. We went by our Garmin route since that had worked so well but the toll roads were mainly 2 lane roads in poor shape. Then again, some stretches were great. It wasn't much fun for the driver but was another fairly short driving day. I'd add that the PEMEX stations were a little farther apart (some were closed) so we paid closer attention to the fuel gauge. There was a military inspection station that pulled us over. They wanted to see all our papers for everything from the car to the dog. We had everything organized and kept handing them stuff and offering more. When they had us open up the back of the Jeep it was so full they just laughed and had us close it. They said something about more paperwork, so I pulled out our binder and asked "You want more papers?" They again laughed and said "no mas." They also really liked our dog Maxx and made a point of seeing his rabies certificate. Again it seemed "These aren't the droids we're looking for - move along!" Tolls ended up costing us $87 USD from Laredo to Chetumal and it was well worth it. Wish we'd had some time to explore Chetumal. Speaking of tolls, that was our only real shakedown. We were running low on pesos and paid for a toll with a credit card. No problem there. The next toll, the agent said the card didn't go through so we paid cash. Turned out the card had gone through so we guess the clerk pocketed our cash. Oh well, it was only about $3 USD but lesson learned.
The biggest problem of the trip was leaving Mexico. We had obtained our FFM's online and it made us pay to get them. When we tried to leave, they said we weren't supposed to have paid ahead, it was only for the northern border with the US that you can use the online visas (which it didn't say), and the Laredo official had taken the bottom of the form and left us with the top when it should be the other way around. They debated for almost 45 minutes before deciding to send us along with a stern warning not to do that again. Whew! Our new landlord said it was probably to get a tip so we gave them one. It was a genuine issue not a shake down so don't get your tourist visa online! Our dog was overheated by then but thankfully BAHA was really nice to us and him. It took us a couple hours at our new place to cool Maxx down but he's doing well now. Sorry that was so long but with time we'll forget details. In fact, that reminds me that most places we stopped were completely out of toilet paper. Bring some with you or some tissues and you'll be happier.
Hope that helps someone. Thanks to all the people who shared their knowledge and helped shape our trip. Cheers!