[jime57]

I agree with the others. You should cover the left over grill pieces, perhaps in back with a piece of black coroplast. That would retain the look, which is very nice.

While on coroplast, I'd be very tempted to add a flat coroplast sheet across the bottom of the spoiler reaching back to the oil pan. That would smooth things out considerably on the underside. Leave a bit, an inch or so, of the flat sheet to protrude in front of the botton spoiler edge. I'm seeing this little splitter more and more on race cars. I think it might help keep a bit of air from getting under the car.

Very nice discovery. You have a good eye!