I would like only to suggest you to take in conideration also the way the new counter will be mounted on the wheel spindel.
I say this because I had some trouble to find how to mount my actual JOL counter on a bike, I was able to do it only with the 3th bike I tried and after modifing a little the gear hole (enlarged).
The first 2 bikes was a Cannondale Road Bike and a Cannondale MTB, where it was impossible to mount.
Regards,
Fabio