Performing a wheel swap can get pretty involved, it's often easier to swap out an entire front end than to adapt a spoked wheel and disc brake to your present forks. Rear drum brakes are pretty simple...wheel center and chain line, but when you get into disc brakes things get more complicated.
I've heard there is some match-up between some Kawasaki and Triumph bikes in the early 2000s, I'm not sure how early that goes. Maybe get some measurements from a Triumph Thunderbird (triple) from the 1990s?