Carbed SS tach replacement?

So in all my experince working on bikes and car I have never replaced a tach on a ducati with an aftermarket one or on any twin. The question is does anyone know much about the signals that the coils from an ss put out? I am working on picking out some new gauges because of a front end conversion and figured I would go with an electric rear speedo pick up. Although replacing the tach is not prefered I would like matching gauges. I am just worried about getting a set of guages and them not working properly because they are likely designed for a 4 cylinder. Any direction or guidance would be great.