at one time we (members ) cut off the part inside the grille that forced the air up, (it really keeps the air in ,,,looks like it would work to get more air into and through the grille,,,, well the ones of us that race our cars every week or so ,found that the air would then bounce back OUT and not go through the radiator the angle of those fins keeps the air from bouncing out,,it forces the air through the rediator and runs cooler ,,,with a stock thermostat u will not see any change on your factory gauge with a aftermarket gauge some times u will see 1 to 2 degrees higher,,with fins removed,, that is when u are going over 100 mph for while. now if you have a show car and have lights in the grille then cut,(remove ) just the 1/2" or so of the fin that is the most rear of the grille jim