FIND
Addicted CEG'er
I think you could just add a switch on your throttle much like you would use for nitrous, to engage the electromagnetic clutch on the supercharger at certain throttle positions, such as putting a switch at 80% throttle.
Another idea would be to run a twincharger setup on your vehicle, if you could find the room. IE mount the supercharger and do a turbocharger setup as well. Then you could use a standard RPM switch to disengage the supercharger as you reach higher RPMs and your turbocharger would have been spooled up. That would give you the many ponies that your supercharger gets, but save your gas milage by transitioning to the turbocharger and disengaging the supercharger. Less parasitic drag.
Another idea would be to run a twincharger setup on your vehicle, if you could find the room. IE mount the supercharger and do a turbocharger setup as well. Then you could use a standard RPM switch to disengage the supercharger as you reach higher RPMs and your turbocharger would have been spooled up. That would give you the many ponies that your supercharger gets, but save your gas milage by transitioning to the turbocharger and disengaging the supercharger. Less parasitic drag.