Ted,
I'm not too sure this would work, due to the spacing of the buttons. With a single breasted jacket the buttons are one inch in from the edge. With a double breasted jacket they are about five inches in from the edge. Because of the radical cut away of a day wear kilt jacket a double row of buttons, even three inches in from the edge, would probably detract from the graceful lines of the jacket.

Like you said, the best way to see if it works is to pin them on and see how it looks.