dogboy: I did it like you said, and similar to how sparkdic did it.
First, I used a die grinder with a 3 inch cutoff wheel on it to cut the center section out. Then I cut pieces of the center section and glued them behind the holes that were left. Then I glued pieces on top of those to set flush with the grill. Pipe glue works the best.
I used a little Bondo to fill in the gaps that were left, then sanded and painted it.
I bought a piece of expanded 3/4" steel, painted it black and fastened it in with a few zip ties. I wanted to use expanded aluminum cause it's lighter and won't rust, but I couldn't find any. I also looked for a 2000 f150 honeycomb style grille, but couldn't get one cheap enuff.
However, I have about $20 in the grille, and a few hours of time. And I think it looks great.
I put on a set of clear corners today. When I get my 31's on it. I'll post another pic.