advice
Your RMX is the weapon of choice for this place. I to have an 93 RMX250.
Gas shouldnt be a problem for you.The larger tank will do fine. Its the MX bikes with the 2.0 gallon tank thats the concern. Roll off's are highly recommended. Camel Bak or water is a must. Tools I took along vise grips, screw drivers, some 8,10,12,14mm wrenches. take spare plugs. I kid you not I would give away at least 3 plugs per ride I always carried 6 plugs. I had guys give me 5 bucks for a used plug. I had copies of my medical cards and 20.00 in my helmet, Slip it under the back portion of the liner. Put them in a baggie. Rocks will be on the trail. 14-15 pounds of air in the tires. Make sure your bike is mechanicly sound. safety wire your grips. Bark busters are nice.
water proof your air intake. The RMX is set up for the run. I had extra levers for my Rmx. Zip ties are a good thing to have. duck tape the top of your boots, Ask Peer about this...lol look at you master link. I must have seen over the many rides at Salamanca 30-40 bikes that tossed the master like clip, Must be all the clay wears them out.