Rather than try to undertake such a difficult task, why don't you make the couple a wedding quilt using the dresses you were thinking of using to make her dress? You could choose a simple block without triangles, ect, even a modified 9 patch that could showcase the wedding dress material in the center and then be surrounded by cotton material that would match either their wedding colors or their home decor. It would probably be well received and still share your family history with the couple.