Can't get Gui Pos on top of Enemy ingame!

Hello Unity Community i Have this huge problem.. i'm making an multiplayer game, everything works exept from the enemy's healthbar on top of his head from the other players view.. i can't get the position right!!

Anyways, heres the script:

 using UnityEngine;
 using System.Collections;
 
 /// <summary>
 /// This script is attached to the player and it draws the 
 /// healthbar of players above them.
 /// 
 /// This script accesses the HealthAndDamage script for 
 /// determining the healthbar length.
 /// 
 /// This script is accessed by the PlayerName script.
 /// </summary>
 
 
 public class PlayerLabel : MonoBehaviour {
     
     //Variables Start___________________________________
     
     //The health bar texture is attached to this in the inspector.
     
     public Texture healthTex;
     
     
     //Quick references.
     
     private Camera myCamera;
     
     private Transform myTransform;
     
     private Transform triggerTransform;
     
     private HealthAndDamage HDScript;
     
     
     //These are used in determining whether the healthbar should be drawn
     //and where on the screen.
     
     private Vector3 worldPosition  = new Vector3();
     
     private Vector3 screenPosition  = new Vector3();
     
     private Vector3 cameraRelativePosition = new Vector3();
     
     private float minimumZ = 1.5f;
     
     
     //These variables are used in defining the health bar.
     
     private int labelTop = 18;
     
     private int labelWidth = 110;
     
     private int labelHeight = 15;
     
     private int barTop = 1;
     
     private int healthBarHeight = 5;
     
     private int healthBarLeft = 110;
     
     private float healthBarLength;
     
     private float adjustment = 1;
     
     public Camera Shooter;
     
     
     
     //Used in displaying the player's name.
     
     public string playerName;
     
     private GUIStyle myStyle = new GUIStyle();
 
     //Variables End_____________________________________
     
     
     void Awake ()
     {
         //This script will only run for the other player characters.
         //We don't need a health bar being drawn above our own player in
         //our game.
         
         if(networkView.isMine == false)
         {
             myTransform = transform;
             
             myCamera = Shooter;
             
             
             //Access the HealthAndDamage script.
             
             Transform triggerTransform = transform.FindChild("Trigger");
             
             HDScript = triggerTransform.GetComponent<HealthAndDamage>();            
             
             
             //The font colour of the GUIStyle depends on which team the 
             //player is on.
             
             if(myTransform.tag == "BlueTeam")
             {
                 myStyle.normal.textColor = Color.blue;    
             }
             
             if(myTransform.tag == "RedTeam")
             {
                 myStyle.normal.textColor = Color.red;    
             }
             
             myStyle.fontSize = 12;
             
             myStyle.fontStyle = FontStyle.Bold;
             
             
             //Allow the text to extend beyond the width of the label.
             
             myStyle.clipping = TextClipping.Overflow;
             
         }
         
         else
         {
             enabled = false;    
         }
     }
     
     
     // Update is called once per frame
     void Update () 
     {    
         //Capture whether the player is in front or behind the camera.
         
         cameraRelativePosition = myCamera.transform.InverseTransformPoint(myTransform.position);
         
         
         //Figure out how long the health bar should be and to avoid a mathematical error set
         //the health bar length to 1 if the the player's health falls below 1.
         
         if(HDScript.myHealth < 1)
         {
             healthBarLength = 1;    
         }
         
         if(HDScript.myHealth >= 1)
         {
             healthBarLength = (HDScript.myHealth / HDScript.maxHealth) * 100;    
         }
     }
     
     
     void OnGUI ()
     {
         //Only display the player's name if they are in front of the camera and also the 
         //player should be in front of the camera by at least minimumZ.
         
         if(cameraRelativePosition.z > minimumZ)
         {
             //Set the world position to be just a bit above the player.
             
             worldPosition = new Vector3(myTransform.position.x, myTransform.position.y + adjustment,
                                         myTransform.position.z);
             
             //Convert the world position to a point on the screen.
             
             screenPosition = myCamera.WorldToScreenPoint(worldPosition);
             
             
             //Draw the health bar and the grey bar behind it.
             
             GUI.Box(new Rect(screenPosition.x - healthBarLeft / 2, 
                              Screen.height - screenPosition.y - barTop,
                              100, healthBarHeight), "");
 
             GUI.DrawTexture(new Rect(screenPosition.x - healthBarLeft / 2,
                                      Screen.height - screenPosition.y - barTop,
                                      healthBarLength, healthBarHeight), healthTex);        
             
             
             //Draw the player's name above them.
             
             GUI.Label(new Rect(screenPosition.x - labelWidth / 2,
                                Screen.height - screenPosition.y - labelTop,
                                labelWidth, labelHeight), playerName, myStyle);
 
         }
     }    
 }

I'v got no errors, the "bar" just flies around like crazy.

please help! Thanks in advance.

Skalde