selecting prefabs

I have a control script attached to each of my prefabs and was wondering how to select each one individually and be able to control each one depending on which was selected.

You can use the same tag for all objects that have this script, then get them in an array at Start. When one of them is clicked, iterate through the array enabling the clicked object and disabling all the others (camera script):

var others: GameObject[];

function Start(){
  others = GameObject.FindGameObjectsWithTag("MyTag");

function Update(){
  if (Input.MouseButtonDown(0)){
    var hit: RaycastHit;
    var ray = camera.ScreenPointToRay(Input.mousePosition);
    if (Physics.Raycast(ray, hit) && hit.transform.tag == "MyTag"){
      for (var obj: GameObject in others){
        var isMe = (obj==hit.transform.gameObject); // isMe is true only for the hit object
        obj.GetComponent(ControlScript).enabled = isMe;

I believe that you basically must set all your prefabs control scripts as DISABLED on start.

Then whenever your ‘activator’ and ‘deactivator’ kick in (for example OnMouseDown and OnMouseUp) you just enable and disable the script back again!