Good point. When the real ones were made. the metalworkers were essentially sculpting in sheet aluminium. That, I think, is why it is difficult to do in a Nurbs modeller. Sculpting type operations are better done in Sub-D.

Here's one attempt



I think I'll try one with a thicker area for the blend...

Tightened it up a bit.. Working on blending it into the body towards the back.