M3-SRT8 wrote:
Yeah, maybe you can cut up a mid 70's Leisure Suit. 
You could, but those things are flammable!
Edit: Bob, I went back and looked at your before/after pix of the grille cloth. From my house, that stuff almost looks like burlap, although yours does not have the regular weave of burlap. Might be a possibility. There should be a light colored burlap. Dyeing, bleaching, etc. might be part of the process. I used brown once in a former life for speaker grille cloth.