Select Enemies(Raycast) -> Display Child Quad with circle base

I have been able to select enemies with the below raycast script, however when each enemy is selected, I want to give the user feedback which enemy is selected. (i.e. a Ring around the base of the enemy) I have been unable to create, find a solution, so asking for help / ideas to keep me going.

Currently I believe that enabling the mesh renderer on the quad will be the easiest way to do this, but I am disabling the parents renderer instead of the quad Child.

function Update() 
{
	if (Input.GetMouseButtonDown(1)) //Right CLick
	{
		var ray = Camera.main.ScreenPointToRay (Input.mousePosition);
		var hit : RaycastHit;
		if (Physics.Raycast (ray, hit, 100)) 
		{
			Debug.DrawLine (ray.origin, hit.point);
			Debug.Log (hit.collider.gameObject.name);
			
			var es = hit.collider.gameObject.GetComponentInChildren(MeshRenderer);
			es.enabled = false;
			

		}
	}
}

If you think there is a better way to do this, please let me know, or point me in the right direction.

Image of Quad Location Setup (As a Child under the Cube GameObject)

So you have selection quads on every unit?
No need - just have one selection object that you hide/show and move around.

// show
selector.transform.position = hit.collider.gameObject.transform.position;
selector.setActive(true);

// later hide
selector.setActive(false);