Route textures do not use attachment points. They are added to the mesh by using the label "route.texture" and in this case, another KUID would be able to change the textures.
Animated route textures would require animation to the body mesh, like on Magicland's R46 GOH. Using the same technique I mentioned above, only in this case, the body mesh is animated around the LCD/LED screens, and will display the different signs. Since the M7 wasn't built with animated route textures in mind, they cannot be implemented.
You would need to contact the original author and see if he can add them, or ask his permission to modify the mesh, if he gives it to you, and then you will have to make, and animate the screens in Gmax or 3DS Max.