I'm currently having problems fixing these two errors. I understand what is causing the error but I'm not sure what i can do to stop it from doing so. Any help is appreciated.

Edit: The use of "public UnityEngine.GUIStyle style = null;" worked. No errors when I used that.

1 Assets/Scripts/BulletFireScript.cs(39,21): error CS1502: The best overloaded method match for UnityEngine.GUI.Label(UnityEngine.Rect, string, UnityEngine.GUIStyle)' has some invalid arguments #2 Assets/Scripts/BulletFireScript.cs(39,21): error CS1503: Argument #3' cannot convert GUIStyle' expression to type UnityEngine.GUIStyle'

 using UnityEngine;
 using System.Collections;
 
 public class BulletFireScript: MonoBehaviour {
     
     public Transform Bullet;
     int shots = 5;
     int maxshots = 0;
     //public Font myFont;
     public Rect position = new Rect(200, 15, 150, 25);
     public string text = "Ammo:  ";
 
     public GUIStyle style = null;
 
     // Use this for initialization
     void Start () {
         Screen.lockCursor = true;
     }
     
     // Update is called once per frame
     void Update () {
 
         if (Input.GetButtonDown ("Fire1") && shots > maxshots) {
                         Instantiate (Bullet, transform.position, transform.rotation); 
                         shots--;
                 }
             else if(Input.GetKeyDown(KeyCode.R))
             {
                 
                     shots=5;
 
             }
     
         }
 
     private void OnGUI(){
         //GUI.skin.font = myFont;
     //GUI.Label(new Rect(20,20,100,20), "TEST" + shots);
         GUI.Label(position, text, style);
     }
 
 
 }