the edge of the front door should not be so pronounced (orange arrows and yellow circle). On the first draft, the door sits on the front. In the prototype, the door is almost flush and only a narrow joint can be seen.
See pictures from prototype.
For the design of the roof I still have to look for drawings. There are not many pictures from above.
But there are enough other pictures, also of the driver's cabs and interior views.
Here is a flickr page about the Class 28: https://www.flickr.com/groups/1354376@N20/pool/
Buffers can be obtained ready-made from component suppliers. Here is an example from David J. Parkins: [url]https://www.djparkins.com/product.php?productid=18239&page=3[7url]
I don't really like them, I would rather have something built together and with a spring inside. But I'm sure I'll find something later.
Couplings and brake hoses should be easier, Couplings are available from CPL Products, among others.
Best greetings, Torsten