I've done 100's of king pin bushes, use a hydraulic press to get the old bushes out and the new ones in.
The holes in new bushes are under size by design, (they don't compress as they are inserted), they are ment to be reemed out once inserted into the stub axle so as to have the top and bottom bush alinged, taking into account any variation in the lenght of the stub axle tube.
Jim
