I need to know the lower profile difference between the 00-03 bumpers and the 04 bumper. The lower attachment points look largely the same although I believe the AP1 uses all bolts intsead of the 3 plastic pins in the center. How about the shape. If you had a front splitter to mount would it mate up to existing holes and shape of the earlier cars or is the profile way different?

 

No, they are different shapes. The Ap1 is angular, the Ap2 is rounded.

 

 

So the diffuser would not fit at all?