Welcome to the Bunnings Workshop community @williamperram. It's wonderful to have you join us, and many thanks for your question about removing a stone shield.
If you can upload some images of the stone shield, including any of the fixings holding it on, I trust our clever members will then be able to advise on its removal. Are you finding it hard to see how it's connected or locate the fixings? Typically you'd find the fixings at the points where the shield attaches to the vehicle.
Let me know if you need assistance uploading those images.
I'll be keenly awaiting those images and am eager to provide further advice.