DecalBumpSpecular Shader (not quite working)

Hello Everyone,

I am trying to create a BumpedSpecular shader that also has a Decal layer and I cant seem to figure out how to get one working. I need it so that I can add some details to buildings that share a tiled brick texture.

Here is what I have so far using the source for the built in shaders...
//////////////////////////////////////

Shader "DecalBumpSpec" {
Properties {
_Color ("Main Color", Color) = (1,1,1,1)
_SpecColor ("Spec Color", Color) = (1,1,1,1)
_Emission ("Emmisive Color", Color) = (0,0,0,0)
_Shininess ("Shininess", Range (0.01, 1)) = 0.7
_MainTex ("Base (RGB) Gloss (A)", 2D) = "white" {}
_DecalTex ("Decal (RGBA)", 2D) = "black" {}
_BumpMap ("Bumpmap (RGB)", 2D) = "bump" {}
}

SubShader {
Material {
Diffuse [_Color]
Ambient [_Color]
Shininess [_Shininess]
Specular [_SpecColor]
Emission [_Emission]
}
Pass {
Lighting On
SeparateSpecular On
SetTexture [_MainTex] {combine texture}
SetTexture [_DecalTex] {combine texture lerp (texture) previous}
SetTexture [_MainTex] {combine previous * primary DOUBLE, previous * constant constantColor [_Color]}
}
UsePass "Bumped Specular/PPL"
}

Fallback "VertexLit", 1

}
//////////////////////////////////////////////////

When I comment out the -UsePass "Bumped Specular/PPL"- the decal works, but when I leave it in it is overriding the Decal texture and just giving me the BumpSpec.

I have tried several other things but this seems to be the closest I have gotten to achieving the result I am looking for. Funny thing is, this was also the simplest attempt.

If anyone knows why this is not working, or if you already have a DecalBumpSpec shader, please let me know. I am also very new to this whole shader thing...just so you know.

Thanks in advance,
AustinJ