Substantial changes to your existing employment can provide good cause to quit. The fact you currently travel to a city in MT is the only relevant fact. Just because you travel doesn't mean you have to travel to NV or CA or even some other city in MT. If the job is beyond the distance prescribed by your state from your home, it's unsuitable if treated as a refusal or would be a good cause quit if the change in location is caused by your employer.

However, you'll possibly carry a burden for proving that you made an effort to negotiate a more favorable work location to remain employed and that the only two options given to you were in NV or CA. I suggest you try to get this stuff in writing because it's amazing what an employer might say if only done verbally.

I collected unemployment going the substantial change route. I didn't get my first unemployment check until 363 days after I quit. I went through two deputy determinations, two tribunal appeals, and three board of review appeals. I had a rock solid case, and still lost a bunch of times. So weigh this very carefully. You may be eligible for UI for all the right reasons, but if you are counting on the UI check, it may not come when you need it, or you might not be the kind of person that can deal with red tape.