OK - here is how I think it needs to work. The turbine runs at 60k and the output is 12k. There is a gear kit available that further reduces the output to 6k.
Next, a pully style CVT will work, but it has to be modified. First the engine needs to have a speed control/governor unit that idles at maybe 4500 RPM output speed and then runs up to 6000 RPM in the same way the helicycle does through a pot. The drive pulley on the CVT needs to have a stall of maybe 5500 RPM so that it does not engage until the engine crosses this RPM. Now, on a normal "snowmobile" CVT the increasing RPM makes the pulley compress to a higher gear ratio. This will not be possible of the turbine since it will run a constant RPM, so instead the pulley must change gear ratio mechanically either through a direct linkage through the gas pedal or some type of fast-response elctro-mechanical device. As the drive pulley increases in gearing the driven pulley will automatically change ratio as well. Finally, an overunning clutch would have to be installed to immediately release driving power to clutch once the throttle is disengaged. The trick will be designing and building the mechanical mechanism to make the driving pulley increase and decrease in gear ratio.