How to use Vector 3 Z position as a range?,Trying to do a Vector3 spawn range for position Z

Hello,

I am trying to create spawn range that spans across the x range, same y position, and a z range. I was able to get it to span across the x range, and the same y position but i cant figure out the z range. I was hoping you guys can help? Here is my code:

 // Start is called before the first frame update
 void Start()
 {
     InvokeRepeating("spawnPowerUps", gameDelay, spawnInterval);   
 }

 // Update is called once per frame
 void Update()
 {
     
 }
 void spawnPowerUps()
 {
     int powerUpIndex = Random.Range(0, powerUp.Length);
     Vector3 spawnPos = new Vector3(Random.Range(-spawnRangeX, spawnRangeX), (spawnPosY), (-spawnPosZ, spawnPosZ));
     Instantiate(powerUp[powerUpIndex], spawnPos, powerUp[powerUpIndex].transform.rotation);
 }

}

The spawnPozZ will not accept that entry I used.