Thank you for the suggestions. I did not know about the Reboxx wheelsets, or that they made the axle tool. But so far it seems nobody else has done this conversion. I might have to commission NWSL to make special wheels. My cheap caliper makes me uncertain exactly what to request. The shortest common axle length is the Atlas at 0.944", which could fit, but I would have to figure out how to drill out the sideframes. I have found no other use of 0.890" axle, the shortest so far being an English P87 at 0.915". Indeed maybe the problem is mainly the deep flanges at nearly 1mm. Maybe I will sacrifice one car to experiment. I think maybe I was hoping Bachmann had upgrades, There are at least to versions of the set, one with links, the other with X2F trainset couplers.