Problem with Fading out Objects via setting rendering Modes to Transparent instead of Opaque

I am working on a scene in Unity. I have a lock. I have a script that causes the lock to fade out.

However the Lock is made up of 3 Pieces. Each of them having their own Materials. In order to have them fade out I must have their rendering mode set to Fade, Transparency, or Cutout.

If I have the rendering mode set to Opaque, alpha values are not changed or effected.

The problem is that now objects within objects are rendered incorrectly, I can see through some of the lock. How can I stop this. Do I need to set the Z sort order somehow programmatically? I can do that, I just need to be pointed in the right direction.