How to shoot in different directions with different keys?

Well i made a Mario-esque game, where i can run, jump and shoot. Well the problem here is the shooting part. When i shoot, i either shoot forward, or out into 3D space. For the shooting script i got:

var Char_Bullet : Transform;
var power = 2000.0;

function Update () {
if(Input.GetKey("k")) 
{
var bullet =
Instantiate(Char_Bullet, GameObject.Find("Gun_Spawn").transform.position, Quaternion.identity);
bullet.rigidbody.AddForce(transform.forward * power);
}
}

What i want to do is, have 'J' and 'L' be the direction i fire in, while 'K' is the fire button. This script only shoots with 'K' and that is, like i said, into 3D space. Any help would be appreciated.

It depends a bit on how your world is oriented along the axis, but basically change the `transform.forward` to `transform.right` (and for other way negate power) and you probably are shooting in the right direction.

Okay, without doing anything smart the code would end up something like:

var Char_Bullet : Transform;
var power = 2000.0;

function Update () {
    if(Input.GetKey("j")) 
    {
        var bullet =
Instantiate(Char_Bullet, GameObject.Find("Gun_Spawn").transform.position, Quaternion.identity);
        bullet.rigidbody.AddForce(transform.right * -power);
    }
    else if(Input.GetKey("l")) 
    {
        var bullet =
Instantiate(Char_Bullet, GameObject.Find("Gun_Spawn").transform.position, Quaternion.identity);
        bullet.rigidbody.AddForce(transform.right * power);
    }
}

That helps to shoot to the right. This still leaves shooting to the left not working. Could you please explain how to negate the power? Because simply making it less or even a negative, it just randomly sprays the bullets.