There is also nothing wrong with eyeballing it, place the object manually to get the best approximation you can.
For the armature, it will all depend on what you want. If you are rigging the train then you want all the controllers to be in the same place. With an armature you will get all your animation data stored in one single place I believe? Also is just the “right” way to go, the legit way, organizational-wise, since the objects themselves shouldn’t be the holders of the animation. It’s best to have an empty parented at least. Why, well that’s the thing you’ll learn on the Animation and Rigging Fundamental courses.
