Chuck,
Diesels are hooked up front to back, back to back, front to back to front, almost any way concievable. They are also sometimes put into the middle of a train or at the rear as "helpers". Steam engines were also cut in the middle of a train or at the rear as helpers in the past.
As for front to back steam engine hookup, I have no knowledge of that. My guess is that both or more steam engines would have to be hooked facing in the same direction so the engineers could see clearly to adjust their locomotive to the others when doing multiple lashups. Remember, diesels can all be controlled from the front loco by one engineer with all the electronics involved, while steam engines had to be under the control of one engineer for each unit.
I also believe that if it bacame necessary, steam locos could be hooked together front to back to pull a train. Remember "The Great Locomotive Chase" of the Civil War? It was true you know. The Texas running backwards actually caught the General running forward. So it is possible for the steam engines to run just as fast in reverse as forwards. However, it is not as safe.