can´t link a gui text to my script

hey guys im new to unity and i got the following problem : (i use unity 5.0 so i didnt found any usefull tutorials) i want to edit a GUIText with my script but when i try to link my GUIText to my variable in the script it basicly do not work and im not sure what i did wrong (i already did it with a normal sphere and it works so basicly i know how it is supposed to work) would be rly nice if u can help me out:) (here is my script may i did there something wrong aswell)

the script is about moving a sphere and collect some objects so your score increases and yeah the i cant eddit the guitext to display the score using UnityEngine; using System.Collections;

public class PlayerMovement : MonoBehaviour { private int count; public GUIText countText; //this is the variable i want to be linked public float speed; public Rigidbody rb; void Start() { rb = GetComponent (); count = 0; countText.text = "Count: " + count.ToString (); } void FixedUpdate () { float moveHorizontal = Input.GetAxis ("Horizontal"); float moveVertical = Input.GetAxis ("Vertical"); Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical); rb.AddForce (movement * speed); } void OnTriggerEnter(Collider other) { if (other.gameObject.tag == "Pick-Up") { other.gameObject.SetActive (false); count = count + 1; countText.text = "Count: " + count.ToString (); } } }