Fasten a piece of transparent foil (big enough, at least 130 x 70 mm), with tape on the side-view of the drawing.
The intention is, that all the views of the locobody (sidefaces + frontfaces + roof)
to be transferred to the foil,
by "engraving" the foil surface. All the views are in one piece,
that means it must goes into the peace of foil.
All contures (windows, ventilator grilles, doors etc.) are to be engraved by a scalpel. Not too hard, otherwise you can
carve trough the foil!
The back of the ruler is suitable as an edge, to engraving against.
The edge bodyside-roof is sensitive - try out engraving on a sample-piece of foil, to get the correct deep for bending
the edge.
The begnning and end of the curved corner between locoside-cabfront: in this stage, just indicate it with a permanent
fine marker.
Cutted out and bended!
You can carefully bend the corners of the cab with a rounded tong.
To get the rounding of the roof: bend it carefully step by step (with help of the edge of a ruler) into the same shape as
on the drawing.
Notice the openings for the buffers, and that the ends of the locobody (the cabsides) are become slightly narrower
from a straight line behind the cabdoors.
The "forehead" over the windscreens on the front end (missing at the picture!) is moved a little bit backwards (0,5 mm).
For that reason, you should cut it out and fasten it separate.