Alrighty, then.

I've gathered and bound the neckline with a self-fabric tape (I hope, bias) -- forgetting, like the rusty sew-er I am, to measure the distance from front sleeve seams to back sleeve seams, and front sleeve seams to front. It's plain good luck that I'm only about 1/8 inch off, which is invisible in a garment like this. Not so in flat construction.

Now I have pockets, snaps and a hem to finish.