It looks like this might work.
The alterations I made at the hips and the bust helped the fit. I'm not sure if adding at the top edge was necessary though. I think what I need to do is drop the point at the center front instead. I didn't add anything at the center, but because of the curve around the bust the bit I did add didn't create the nice angle that I was after. I've marked the top and bottom edges with tape, and positioned the cording.
I'm happy with the shape. It takes a little imagination, but I think I'll be able to achieve the smooth, elongated, torso seen on the fashion plates from this era. Yea.
illustration from La Mode Illustree´1888