Mavic 3G Carbon Trispoke Rear Hub

I have an older Mavic 3G carbon trispoke rear wheel that has an old school 8sp screw-on freewheel. I know Mavic made hub conversion kits so that the wheel can be converted for road or track use. But do they also make a kit to convert the the hub from a screw-on freewheel to a cassette type? Or is there an aftermarket kit to do this?

If a screw-on freewheel to cassette conversion kit is unavailable, is there any company that makes a Shimano compatible 9sp screw-on freewheel? If so, where can I find this freewheel - store/online retailer/manufacturer direct?

I would like to use the wheel for local time trials and such but it's not compatible with any of my current rides which use either 9sp or 10sp Shimano DA. I want to make the Mavic 3G at least compatible with the 9sp machine.

Thanks in advance.

 

There must be someone who has an idea.......