Have you e-mailed Mike Drew (MikeLDrew@aol.com)? I'd also try Don Byars at Full Throttle Panteras +1 (951) 245-7300. I'm sure Don's done more GT5-S conversions than anyone else. Do you like the look of Si rear grilles? The openings in the 5-S and Si rear fenders look the same to me. No, I don't know where there are some Si rear grilles but it doesn't look like they'd be too hard to fabricate/duplicate. I still think your best bet is to borrow a set and have them programmed into Solidworks, or some other CAD design program, then have them 3D printed. The resulting items would likely be better than the originals. They'd certainly be lighter!
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