Based on the fashion plate I am copying, the over dress is very much a polonaise and likely bodice and overskirt are on piece attached at the waist. I haven't quite decided if I am going to do that too or have them as separate pieces. I'm still trying to decide what will be easier.
But the bodice has been mocked up and the skirts draped!
The whole thing still needs to be fitted so there's likely to be a bit more adjusting but the bodice is coming from an old muslin that I had drafted and fitted to myself a ways back, it's the foundation I use for all my 1860s gowns, so it should be pretty close.
The skirts just started out as rectangles and it was just a whole lot of pleat here and tuck there until I had a shape I liked. While I am quite happy with the back I am not in love with the front panels yet . . . I feel like they are too full like maybe I have to much being plated into the waist toward the front. . . Not sure though.
Alright off to the next step!