When i first had the zxr forks i was using mc 18 calipers and had the fork bottoms machined as the discs were as yours are in the calipers , but when i switched to mc28 calipers this needed them to use a spacer as they fit the other way round! Sorry i was being dull earlier.
So you need to have a couple of mm taken off the caliper mount (0r the caliper) on the fork to move them out and centralize the disc.
The vfr discs size was right on for zxr forks, but i did try it with the Nsr discs first and they only touched 2/3 of the pad like you're discribing.
Hope my rambling helps.
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it wouldn't be fun if it was easy!