Available with 3D Analyst license.
You can alter the placement of a 3D symbol in relation to the feature it's symbolizing. You can set the origin of a 3D symbol then offset this normalized origin. In addition, you can alter the rotation of a symbol in the three axes that define 3D space.
When you set the origin of a 3D symbol, you're indicating where on that symbol you want the origin to be. For example, the default location of the origin for a pyramid is at its center. You can set, or normalize, the origin to be at its peak instead.
After you are satisfied with the normalized origin of a 3D symbol, you may want to indicate an offset for the symbol. Real-world units are used to set offsets of 3D symbols. For example, you may want your sphere symbol to be 10 meters above the actual feature position.
The final step in defining the 3D symbol may be to rotate it through one or more of the three axes. For example, you may want to turn the pyramid symbol upsidedown so it appears to point at the feature position below it.