Ken,
Sounds like a dream trip to me
I've been traveling around Baja for many years. The small town people are very friendly and will go far out of their way to help and show kindness. Be friendly and you will get it back 10 fold.
That said, remember there are always bad seeds in any group of people regardless of race, religion or political beliefs, so keep a smile on your face and one finger on the trigger

(just an expression, don't even think of bringing a gun)
Karen's advice was right on except for the $ for mordida imo. If you get stopped always ask to see the judge. Usually this will result in you being excused on the spot with an accompanying excuse. It will never cost you more to see the judge.
I'd add this-
Never keep all your cash on you ($100 max) and don't bring a big cash wad. Have a $200 cash reserve stashed some where. I use my dirty laundry bag

Use travelers checks and cash them in at banks in the citys. Bring a credit card and check all transactions with a calculator for USD-Peso correctness. I like to cash $100 US to Pesos and keep it as my WAM money so I don't have to use the calculator. This is especially helpful the further away from big cities you are. Bring a pocket calculator, it will be very helpful at times.
When you stop, don't leave the truck unattended unless you see a security guard, or a local offers to watch it. Make sure the local is someone who is working nearby or has a business, not just milling around. ALWAYS pay folks who help you, you must understand the local customs and paying for services rendered is a universal custom.
DO NOT drive at night, ever. The big bulls move around at night. Your family's lives are not worth risking. Trust me, you will not be able to stop in time, most often they will dart out from a bush only feet ahead of you. DO NOT drive the highway Sunday evenings. Drunk drivers are not exclusive to the USA.
Learn some Spanish. It will be very helpful. There are many good audio tapes you can buy and listen to in your truck before you go and while on the trip. The locals appreciate it immensely when you try and learn "their" language. Just like we expect people in our country to use English, they will too if they don't speak English. That said, some of the best conversations and friendly interactions have been with locals who speak no English, but go way out of their way to help me. Bring a Spanish to Englisher dictionary, it will be invaluable. Always say thank you when someone helps or shows kindness.
Bring extra fuel filters and a basic tool box. The diesel in Mexico is better than what we have, you'll notice the extra power and fuel mileage. I always have two 5 gallon cans of diesel on board when traveling long stretches between big cities. Go to Cummins website and find the Cummins facilities in Mexico. Very unlikely you'll need them, but they could prove valuable in a pinch. MAKE SURE before you go your batteries, belts and hoses are not old. Do all PMs by the book before you go. Keep the old belts and hoses as a backup. The mechanics in Mexico are incredibly talented at patching stuff together, so besides engine or transmission work, their is not much that could go wrong that they could not fix. Check out the "Dina" diesel busses and trucks, they are legendary for their power
Most of all have fun! I wish I was going

A few days into the trip you'll be "in the groove" and having a blast. Watch out for the Tequila, some of it is soooo smooth you'll be in over your head before you know it
