There is a simple circuit you can use to interface to your tach. I'll dig it up and put it on the website.
With the rev limiter, the only thing I could think of with the EDIS module is to use the 'rev limiter' RPM output and use it to cut power to the coil pack. (the center lead)
Note that I *have not* tried this myself. The output works correctly, but I haven't implemented the rev limiting yet.
To cut power to the coil pack you would either use a solid state relay that can switch DC or use a power transistor circuit. a regular relay would probably not work well.
If you decide to try it out, first test it at a lower RPM setting.

Brent