How's the cardi conversion going?
I'm currently trying something similar. The pattern is for a cable-knit boy's cardi, and I'm turning it into a cable-knit sweater dress for DGD. Luckily the sleeve shaping is the same front and back, so I'm doing 2 backs, and will start the neck shaping for the front when I get to the right point (a bit of trickery will be required I think).
I'm obviously making it longer too, and have done a picot hemline, to be folded back and stitched in place. To keep the cable pattern but to create a slight flare, I started on size 5mm needles, doing the hem and first 10 rows, then did 10 rows more on size 4.5mm, and then the rest up to the neck on size 4mm, which is the right size for the pattern, so that the chest measurement comes out right. I'll probably do a little picot edge to the neck and on the cuffs, to make it a bit feminine.
Just hope it turns out OK. I've got till Christmas!!!