There are no events for you to practice that I know of. The JL school will help more than anything I suppose. But the main thing is to practice time keeping. It is more like enduro racing than the Mexican 1000. You can do that on paved roads around home.
You should get a sample route instructions for one of the TSD stages from previous years. Then lay out a route and carefully make a route chart with similar information as your sample. Then go out and ride it attempting to keep the exact pace according to your chart.
Every route instruction will have a distance from start and an assigned speed. The speed will change every few instructions for whatever reason. Your job it to pass every instruction on the exact second you should be there according to your assigned speed and the distance traveled to the instruction. It's all math unless you have a computer to do the math for you.
I just received my Checkmate Enduro computer from ICO Racing today ($299). I will be making local TSD sections all summer and learning how to program the distances and speed of each route instruction into my computer. Then I'll ride them to see if I am programming correctly. If I am, my instrument will constantly tell me if I'm early or late. That allows me to adjust my pace according to the computer display.
The guys that win this thing practice routes and programming all summer advance of the event. They have it dialed when they show up. Both bikes in 2006 were top five overall including the cars with navigators
. In 2010 my riding partner was teamed up with a top car crew. The car guys trained my buddy in their time keeping system for weeks in advance in the Arizona desert. After the first day, I knew my buddy had a chance to win. I was shocked! It's all about timekeeping. The navigation isn't that tough after you get used to it on the first day.
Not saying these guys didn't have time keeping snafus and maybe a nav error or two, but they were well ahead of the pack from the first stage.
BTW, you talked me into riding my 690R afterall. I'll mount my nav gear on a Touratech crossbar this weekend and start trying to understand the programming.
The Mexican 1000 is a true race. Very long timed sections and the quickest through wins. The speeds are very high. The navigation fairly straight forward. You can use a roadbook or a GPS. Most seem to like the roadbook best because it shows the hazards coming up.
My son raced it last year on a new KTM 350. They were 4th overall motorcycle and 1st in class with one broken wrist and one run out of gas. He is going back this year to race it solo. I'll drive the chase truck. His co-rider is coming back aboard a new 500. Seems they need about 10mph more to compete for the overall win. The 350 was only good for 96mph on the playa.
... The Alcan 5000 is not that kind of event at all.