Pattern Alterations

I'm altering a pattern for a blouse from Marfy #1251, which as you can see has a lapel on one side, and a flounce on the other. So, they give you both a left and a right front piece. I altered the side with the lapel, and will cut both sides from it, and cut off the lapel for the flounce side. You can see my FBA below, next to the unaltered flounce-side front piece.  

Since I bought the pattern in a size for my shoulders, besides altering from a 44 at the shoulders to a 48 for the bust, I also altered the sleeve, which was both too narrow and too short. The bottom edge seamline is the original length, as you attach a band and then a flounce, and I didn't want to have to redraft the flounce, which is of course, a spiral.
I'm beginning to cut this in a deep green silk gauze, which will be sort of a test, as if it fits well, I'd like to try it in a plaid or stripe, which will show the changing grainline on the flounces.