A Better X-Ray
This tutorial will teach you how to use a better style of X-ray in Maya.
Open the file that you want to use to test out this way of creating an X-ray. If you don't have one, you can use this sample file.
Step three - Go to mesh component display and go to backface culling; set it to full.
Step four - You won't see any difference yet. Now go to polygons normals>reverse.
Now you can see the inside faces of the model without the exterior ones. As you can see, when you rotate the camera, the results will be the same. When you're done using it, simply reverse the normals back to normal and set the backface culling to off. One of the biggest advantages to this X-ray over the default X-ray is that you can't accidently select the exterior faces, and it isn't just transparent.