No answers so far, so I did some reverse engineering. The only help I could find was telling me how to achieve a flared sleeve, so I thought that if I did the reverse, I would bring it back to the original shape.
I started by measuring my arm, to get an idea of how much fabric I needed to remove. Then I began drawing straight lines down the sleeve, spaced about an 11/4" apart. I then marked 1/2" at either side of the line at the sleeve hem edge, and cut up, bringing both sides to the centre line. It was tedious, and looks very messy, but it appears to have worked. The sleeve head remains the same width, but the excess fabric has been removed from the sleeve.
I'll use the pattern for my toile, tweak it where necessary and report back, but it does look OK, apart from needing to be trued up around the hemline a bit.
Now to lengthen the bodice....
Jessie