S2 16V 4 to 5 bolt Conversion Brake Disc Question

I am converting the rear brake rotor on a Scirocco16V from 4x100 to 5x100.

Are the Corrado VR6 rear brake rotors the same dimensions as the Scirocco16V discs,
are they interchangable?

If not, what is the proper way to do this.

thx