Another mistake made by one company is the production of Norfolk Southern Heritage diesels using SD-90's instead of SD-70's. Their claim is that it really don't matter as these are just toy trains.
At least Lionel & MTH got the models correct on the diesel engines for NS.
A little FYI on Reading diesels; the Reading used GP-7's, GP-30's, GP-35's and GP-39-2's. They also had SD-45 diesels and some C-630 diesels and a some FM Trainmaster diesels.
There were other diesels the reading used but I can't think of them right now.
Lee Fritz