1. Install TouchXplorer
2. Install HTC Connection Setup
3. Download and extract this zip file to your PC.
4. Deploy the extracted XAP to your device
5. If XBMOD.Files.Deployer does not automatically run, run it from your App list on your device.
6. Using TouchXplorer on your device, copy \My Documents\My Ringtones\CustClear.provxml to \Windows\
7. Run HTC Connection Setup on your device, hit the ok button (with the check mark) to let it provision.
8. You're done.
If you unlock with ChevronWP7, apply this hack, and then for some reason your phone relocks, refer to DanielNTX's post to get it unlocked again. You need to install a new certificate, provided on his post.
All credit goes to xboxmod and his HTC Registry Editing thread and HTC WP7 Apps thread.