The TNX is a awesome basher truck, just run it stock it will be fine.
Here is what you will need, a battery stick pack and a charger for it, to run your electric starter wand. A rechargable glow igniter is nice they last a very long time. Spare glow plugs. You might want to ask other tnx owners, what parts commonly go down on this truck, so you can keep them on hand. All trucks have a weak piece thats prone to wear quicker or break.
In my case its usually the driver that causes the breakage. Hitting poles etc