I seldom say "never" or "impossible" on the forum because someone is sure to prove me wrong, but in this case I'm positive of saying it can't be done in the average home workshop. Today's wheels are so tight on the axles that it's impossible to adjust gauge without bending an axle or breaking a flange. Postwar - yes; modern - no.
If it's really bad, a trip back to the manufacturer is the best way to deal with it.
Jim