Change image Target from url image

in this tutorial https://library.vuforia.com/articles/Solution/how-to-create-and-load-targets-in-unity.html The developers show us how to create a new target that was created after load an image from url.

But if i create a image target, i also put script's and components inside and only want to change the image that activate the target. Any know how to do it?

Or i dont care if change in runtime or if is at start the application.