How can I make auras invisible?

[Indigo]

Gent, I've encountered some Green Lantern meshes that already have their green auras enabled when flying, but I have more Green Lanter meshes that don't have the aura at all, can anyone help me on how to make them invisible thru skinning? 

[apfarmakis]

I'm away from my PC but, from what I remember, you take the aura.tga and add an alpha layer to it and you're good to go.