Is the center to center distance between the hub bearings the same as the center to center distance of the frame bearing holders ? I am pretty sure the distance on a KH frame is 100 mm.
Is the OD of the hub bearings correct ? You can fit a 40 mm hub into the 42 mm KH frame, with a spacer, so that should be less of a problem.
I would measure the bearing center to center distance on the hub, if it's 100 mm, I would think you wouldn't have any real trouble.