I would like to assemble one or two prewar sets. I have thus far the 224E and 226E with the matching tenders. I think I am seeing two different types of pre war coupler - one I think is called a "box" coupler and I'm not sure what the other is called. At least it appears different and maybe earlier. I'm not sure if its compatible with the box coupler or even when it was used.
I think there is an adapter of some kind to go from box coupler to knuckle.