ok, im building a long range desert chevy truck, and well, im a little lost as to how far to bring the weathring, faded paint is a given because of the amount of sun, but what about the lower part of the vehicle. with the lack of water, what does the exaust pipes/muffler do, they probably dont rust right?

any tips on weathering a Desert vehicle will be greatly apprecieated, all i have done so far are more wet climate weathering.

I do have an upcoming half track as well, what would the tracks on it look like?

Subtly is the key.
Alot of desert models I've seen have over-done weathering.

It's a misnomer that metal doesn't rust in the desert. Moisture, in the form of dew, collects almost every morning during much of the year. Remember, the temperature swings in desert environs is among the highest of any type of environment. Plus, most of the fighting in North Africa occurred in a fairly small swath of land bordering the Mediterranean. Humidity in that area was much higher than in the "deep" desert areas to the south. Humidity+dramatic temperature swings will produce condensation. Rust those mufflers just as you would just about anywhere else.
Now, if you are talking about rust streaks from paint chips and the like, I'd assume you'd be safe to forego those.

cool, thanks guys. rust is a go on the muffler, and no rust on the body.