GL.Lines only showing in one eye

Thanks for the reply. I am now and that has now moved the lines to the correct locations in both eyes!

if (Params.riftEnabled)
                {
                    GameObject ovrCameraController = (GameObject)GameObject.FindGameObjectWithTag("ovrcamera");
                    Camera[] cameras = (Camera[])ovrCameraController.GetComponentsInChildren<Camera>();
                    SteeringManager.PrintVector("Cam " + i, cameras[i].transform.position);
                    GL.modelview = cameras[i].worldToCameraMatrix;
                    GL.LoadProjectionMatrix(cameras[i].projectionMatrix);
                }

But I still have a problem which I hope you can see from these screenshots. This is screen without the rift enabled:



And this is the rift enabled screenshot:



If you line up the two screens you will see that the lines in the stereo image are being occluded by the positions of the 3D objects in the non-stereo image. Also in the non-stereo version, if a line happens to penetrate a 3D object, then the 3D object is drawn on top of the line however in the stereo image, the lines are drawn on top of the 3D models.

BTW I tried adding this line:

GL.Clear(true, false, Color.black);

And rather strangely, this partially fixes the problem for the left eye. The lines are no longer getting occluded, but are still getting drawn on top of the 3D models, but it doesn't affect the right eye image.

I feel Im getting close!