Tank Setup Problem

Hey guys, what's up? I need your help, cuz i'm having some problems with a tank setup. I'm making a tank game, and i'm in the alpha stage, but i'm already having problems. Well, i'm trying to setup a tank with the following scripts:

var velocidade = 0.0;

function Update () {

var acelerar = Input.GetAxis("Vertical") * velocidade * Time.deltaTime;

rigidbody.AddRelativeForce(Vector3(0,0,acelerar));

}

and

var velocidadeDeRotacao = 100;

function Update(){

var virar = Input.GetAxis("Horizontal") velocidadeDeRotacao Time.deltaTime;

transform.Rotate(Vector3.up * virar * Time.deltaTime);

}

The first script controls the aceleration of the tank, and the second controls the rotation of the tank. Its working very well, but i want more. I want to controls the tank's body and the tank's tower independently. I'm using a mouse look script in the tower. I want to when i turn around the body, the tower don't move together. So i can control them independently. That's it, thank you and sorry by me poor English, its because i'm Brazillian and 13 years old.

Edit: This is the hierarchy:

Tank(Empty GameObject to correct the axis) Tank (Mesh) Top (Empty GameObject to group the objects below) Canon (Mesh) Tower (Mesh) Main Camera (Camera) Bottom (Empty GameObject to group the objects below) Body (Mesh) Wheels and tracks (Mesh)