Well, thinking I would just get away with my first attempt at the stays with the too long arm straps I was just about to sew them together when I decided to do it right. I undid the binding and cut down the straps and then redid the binding...argh! In the end it worked well enough and now it is done right. You can see the pics in the initial stays entry and the pics below.
Above are the after, below is the before: