[Closed] Shimano splined rotor question.........

I have just purchased a set of XTR splined rotors. My wheels are Planet X super light's which have an adaptor which marries the hub to the current Shimano rotor. Being quite new to this type of set up, I assumed that all I needed to do was to remove the adaptor from the old rotor and replace into the new. That would be too easy, as the fit into the XTR is what I would call interference and not tolerance. The old rotors are RT62's and the new are RT97. Any ideas or am I just missing the obvious?

Any help greatly received.