I had mentioned earlier that I was doing 2 rows of stitching since I was concerned about the fabric fraying. The Stonehenge fabrics aren't as densely woven as say your batik fabrics. I discovered that even with the 2 rows of stitching there were places where the fabric still wanted to fray so I had to leave more fabric from the stitch line until I'm ready to actually do the buttonhole stitch. Here is the Wild Mustang all cut out but when I go to do the buttonhole stitch there will be some additional trimming at that time so that I keep fraying to a minimum. If you look at the top of the horse's mane this is how much will be cut out, while other areas do show more fabric at the moment and the image of the horse isn't as distinct that will change. The areas that did frey I went back and stitched over them a couple of times to keep them in tack.
I have also tested the buttonhole stitch on the sample piece and have determined the appropriate width and length. While running the tests I also realized that even with 2 layers of fabric I still needed to back it with a stabilizer since it was doing some pulling and tugging. So now I'm ready to start finishing the reverse applique with the buttonhole stitch, this will take a few days indeed since that stitch takes time to run and you can't rush it.