U have to cut the ends of the SVT grill to make it fit in the zx3 bumper slut.There's three cross pieces in the stock bumper and u have to cut those same cross pieces in the SVT grill.Try to make a clean cut when u cut the ends of the grill.If u can't get the clean look in the grill,I'd put two alum. pieces in the end and i'd painted them black to match the grill.I hope that help.
If you're willing to wait about a month, I'll have mine for sale. A truck backed into my bumper and put a big hole in the corner of it, so I'm replacing it with an aftermarket one and getting a new upper grill in the process. No damage to the grills at all.