ANYBODY WITH FR500 WHEELS ON COBRA'S?

I just put the fr500 on my 98 cobra, they look alright i want over excited about it but i went for these due to the 17*10.5 in the rear.
Ill get pics up soon. My question is. I got them from mustang tuning the are replicas i understand that but the center caps for the 10.5 dont fit. they are the 2.5 inch caps . But the rear dont fit the caps are too big. Anybody have a suggestion or problem with this.

thanks

andy
www.mid-atlanticracingfuels.com

i figured it out! I put the svt emblem on the original cap that came with the rims from mustang tuning, THEN used a grinder wheel to make the cap the size i needed for the rear wheelsp, I would still like to know why the 10.5 rims have smaller center caps?

thanks
andy