Find the position of text on the screen

I need to be able to find where certain words are on the screen so that I can have a texture cover them. The texture needs to be clickable and when it is clicked the word will change and the texture will become transparent. I've already figured out how to change the text but I don't know how I'd go around finding out where certain words are on the screen.

Here is my code to display the text.

 void Start () 
 {

     textArea = new Rect (20, 20, 650, 250);
     myText = "Apricots simulates the array throughout the unlike courier. A setting bread believes in the congested captain. The party occurrence founds gorillas. Gorillas fuses the projecting praise under the procedure. Under gorillas expands each asking slash. The losing ruler rebuilds gorillas past the ash.";
 
 }

 void OnGUI()
 {
     
     GUI.skin = skin;
     GUI.Label(textArea, (myText + " " + variableButton + " " + myText));
     
 }