So. Here is one of the panels I added to the side of the dress. I only had to increase the bodice; the knit lining is stretchy enough that once I released the dart in the back it worked. I clipped some of the gathering stitches in the chiffony overskirt to release some of the gathers and that worked.
That side panel is pieced up from the 3 1/2" I cut off the bottom, lol. I did my best to cut it into on-grain rectangles, from both the lining/underskirt and the chiffony overskirt remnants, and then I pieced the rectangles to get the length I needed. I used the satin from JoAnn's as the lining for it. My pillowcase is still intact, lol.
At first, I just gathered the overlayer on the side panels and thought I was good, but when I compared it to the dress I realized it needed to be pleated. So, off it came...and I had to cut a couple more pieces from the hem remnant because it needed more fabric. I think I ended up with about 8 rectangles of the chiffon. You *can* see the seams in it...if you look really close...but from any distance it looks like part of the pleating.
I haven't tacked the lining back down to the waist yet; I'm going to do one more try-on to make sure it fits. I did add a pinch more width than the pinned-up ribbon indicated, because that would have been really tight and I don't want to strain the zipper. If it looks too baggy it will be easy to take up a bit in the seams.
I will say it again...I am so glad this is not what I do for a living, lol.
Now...on to my dress....