Wunderkind has come out with a couple great items for the 1600. First a rear Brake lever enlarger with models for both the GT and GTL and second some wide angle mirrors. I have installed both on my GT and have been quite happy with their performance. Always had a hard time with rear brake lever missed it a few times. The mirrors help in the blind spot area and being gold in color has cut reflections a lot
Consider it money well spent