I was up in Two Guns and also went to Canyon Diablo recently. Two Guns has an interesting history, and the "Death Cave" is right below the site of Two Guns. You can visit it. Incidentally, some people are posting the wrong photos for Two Guns, they post photos of buildings that are near the old gas station, and that is just recent buildings. As I understand it, Two Guns is actually on the East side of Diablo Canyon, but right on the side of Diablo Canyon, not over by the old gas station. Also, what is on the west side was built later, including the zoo, (yep, you heard right) that was part of the tourist trap that was started there in the early 1900's.
Canyon Diablo was difficult to get to. After looking at satelite maps, I set out from Two Guns north, and the road was rough, I did it with my car, and it was not easy, with a 4-wheeler it would be a piece of cake until you get to the rail road, then you have to go on foot, because they have the road blocked off with rail cars and a huge pile of dirt. I was not metal detecting there, as I had read the history of Canyon Diablo and knew that people had been buried there. (Later I learned it would not have been a good idea anyway, being on the indian reservation.) While there are some impressive building ruins at Canyon Diablo, the downside is that there is old trash scattered all over the place. They also had some type of in the ground large stone kiln building that had been fired recently, for who knows what purpose. Other than the trains that go by, the place is one of the quietest places I have ever been.