Well now you know MikeSr, there is no more debate, because the facts are now known and testified to by the project engineer in charge of the whole Evolution program Goran Sallstrom.
If you lift the hood and look at your Chassis plate it will have an SO2476 number on the top right hand side of the plate. If you chassis plate does not have that specific dedicated code somebody has converted your cars original Coffin-Nose hood and grill, to a Flat-Nose version before you got to buy the car.
It would also be interesting to know if your car still has the Silver painted grill because all 505 Evolution cars that left the factory were fitted with these Silver painted grill's, many were changed by the original dealer's to the optional black grill with the chrome strip's across the top and bottom of the grill which my own car has, and interestingly the photo of the FIA approved Evolution car has the optional Black grill with the chrome stripes.
All the Factory supported, so called "Works" cars were fitted with the plain Black grill, and each individual "Works" team laboriously cut the back out of grill individual box's horizontal blade's, so that it would pass more air! It took on average 4 hours to do this, and nobody ever proved a quantifiable gain, yet we still did it to each and every grill we had to replace, or when we built up a new car etc.
Mine has the SO2476 plate, but has the black grille with chrome top and bottom bars. The original owner was a Volvo mechanic and kept it in great original condition except for a respray. The car was an original dealer sale in Atlanta Georgia,USA.