Correct Unlit Shader to use when Fading a Material

I have a texture applied to a plane, and wish to dynamically set the alpha. The problem is fading the texture using the alpha channel of material.color, after manually assigning the colour white at start.

I have this script which works when using the default transparent diffuse, but not any of the unlt shaders. The shaders for unlit from owlchemy labs didnt work either, even though I can see the alpha bar moving up and down.

 // START
 theMaterial = gameObject.renderer.material;
 theMaterial.color = Color.white;

 // UPDATE
 theMaterial.color = Color( theMaterial.color.r, theMaterial.color.g, theMaterial.color.b, health * 0.01 );

How do I change the alpha of a texture using an unlit shader? Which shader should I use? Does anyone have a link to a shader (shaderlab and UnityGems are my first call when have time to learn CG and shaders). Thanks =]

Owlchemy Labs Unlit Alpha Shader :

 //Originally by Bill Vinton (Sync1B)
 
 Shader "Unlit/AlphaSelfIllum" {
     Properties {
         _Color ("Color Tint", Color) = (1,1,1,1)
         _MainTex ("SelfIllum Color (RGB) Alpha (A)", 2D) = "white"
     }
     Category {
        Lighting On
        ZWrite Off
        Cull Back
        Offset -1, -1
        Blend SrcAlpha OneMinusSrcAlpha
        Tags { "Queue" = "transparent" }
        SubShader {
             Material {
                Emission [_Color]
             }
             Pass {
                SetTexture [_MainTex] {
                       Combine Texture * Primary, Texture * Primary
                 }
             }
         }
     }
 }