Reply to "Perfection Max Gray U.P. Big Boy"

Be aware that flanges on some MG models were rather tall when compared to those on more recent O scale 2 rail models.   My MG PRR C1 and D16sb models badly bumped through the code 125 turnouts in my yard and branch line track.  They ran ok through mainline code 148 turnouts. In addition to re-motoring and up detailing the brass MG models, I've replaced the wheel sets and had the driver flanges turned down. They now look and run better.    If you do not wish to alter your model and want to run it on 2 rail  track be sure to go with a rail height and turnout frogs compatible with the flanges on your Big Boy.