Antique German 1950's Europa mantle clock.

This is a clock that I've had for a while. It has an unusual striking movement with "alarm clock" type winders. Although the clock is currently overwound, I plan to repair that soon. Another neat feature about this little clock is that it has the original instructions. The chime bell is off the clock, currently, and I was wondering how, as I have not managed to myself yet, does anyone know how I can screw it back on? Thanks!