Jonathan and others. I think it is important to remember that Lionel's offerings are geared to the average modeler, not the true scale rivet counter, and that the models they produce are genetic and not necessarily highly detailed to a specific road names. Even though the E7's appear cookie cutter, each railroad had unique features, most had subtle changes or add-ons that would not be noticed by the average modeler. Unless the modeler has researched the model.
In order to keep costs down, I know that Lionel and others, offer most diesels with the same detail features. Unlike scale suppliers, such as 3rd Rail whose models are more accurate to road specific.
Modifying a production run of an engine that requires additional modifications is costly.
So even though the Lionel E7 in GN or CB&Q or any other road name for that matter, lacks road specific details, I think they capture the essence of the prototype.
Most true scale modelers will either operate 2 rail, or if they choose 3 rail, will most likely stay with high end suppliers, or will modify the stock equipment offered by Lionel, MTH, Atlas, Weaver, and others.
Ray