ignore select collider

I have a tower object with two colliders - a box to represent its actual physics, and a sphere to represent it’s range. I want to test for the box, not the sphere, however both exist on the same layer(as they’re part of the same object). Is this possible at all?

Tower
Box: Not trigger.
Rigidbody: Kinematic
Sphere: Is Trigger

Other object:
Box collider: Not trigger
Rigidbody: not kinematic

Relevant Code:

var moveVect : Vector3 = Vector3(1, 0, 0);
var moveSpeed = 32.0;

function Update () 
{
	var hit : RaycastHit;
	
	
	if(Physics.Raycast(transform.position, moveVect, hit, 1))
	{
		if(hit.collider.GetType().ToString != "SphereCollider")
		{
			print(hit.transform.name + " @ " + hit.transform.position.ToString());
			transform.Rotate(Vector3.forward, 90); 
			Debug.DrawLine(transform.position, hit.transform.position, Color.white);
		}
	}
	transform.Translate(moveVect * moveSpeed * Time.deltaTime);
}

Just make the sphere a separate GameObject and assign it as child to the tower. This way you should be able to set it’s layer separately and/or just identify it by it’s unique G.O. name/tag/whatever.