So from what my mechanic says my 08 stype non Brembo standard brakes have 305-310 mm rotors front and back and the OTHER standard brake option that year had larger 326 mm rotors front and back with correspondingly larger calipers. My question is did the smaller rotors and the larger rotors MOUNT using the same hard points or were they of a completely different design. If they mount in the same way I’d like to use the 346 mm from and rear rotors I bought by accident, and just go buy the larger calipers if they’ll mount the same way. Are the swappable?

thank for any an all help.

2008 stype 3.0 satin edition 67000 miles basic base sedan.

 

I have no idea if they can be changed.
However in my opinion it is best to stick to the factory size rotors and put your accidental purchase down to experience.

There will be no noticeable difference in the braking if you use the smaller or larger rotors

But others may know more.

You can also use the official on-line parts catalogue to look up to see if the part numbers are the same:
https://parts.jaguarlandroverclassic.../brand/jaguar/