Dear Mr. Bachmann:
http://www.mylargescale.com/Community/Forums/tabid/56/aff/23/aft/125764/afv/topic/Default.aspx
Bruce Chandler posted an add for the Hartley & Teeter light inspection cars at the above web link and built a model using the Bachmann Gandy Dancer drive.
A suggestion for a future Bachmann product !
Norman