Norge front disc fitment

[Bison]

Hello Folks,
I'm looking at EBC numbers for my 2007 Norge ABS front disc fitment, the ones that are on now are MD624, the ones that are widely available at better prices are MD2003X. My question is, what's the difference?, is it only the pre drilled holes for the ABS ring?, or did Guzzi in their infinite wisdom change the disc dimensions on the later models?.
Right now though, the sun is shining and it's well above zero degrees, so I'm going out for a ride!
Thanks,
Alan.