How do I fix my Roll-a-Ball Count text output?

I followed the tutorial and rendered a GUItext and my code is exactly the same, with the exception of adding using UnityEngine.UI; at the top. When I press play, I get:

Count: GUIText(UnityEngine.GUIText)

I looked at other answers and I couldn’t find the answer to this one. Here is my code:

using UnityEngine.UI;
using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour 
{


	public float speed;
	public GUIText countText;
	private int count;

	void Start()
	{
		count = 0;
		SetCountText ();
	}

	void FixedUpdate() //For Physics
	{
		float moveHorizantal = Input.GetAxis ("Horizontal");
		float moveVertical = Input.GetAxis ("Vertical");

		Vector3 movement = new Vector3(moveHorizantal, 0.0f, moveVertical);

		rigidbody.AddForce(movement * speed *Time.deltaTime);
	}

	void OnTriggerEnter(Collider other)
		{
		if(other.gameObject.tag == "PickUp")
			{
				other.gameObject.SetActive(false);
				count = count + 1;
				SetCountText ();

			}
		}
	void SetCountText()
	{
		countText.text = "Count: " + countText.ToString();
	}
}

line 41 - countText is a GUIText so you are trying to convert that to a string. Maybe you need countText.text?