Upload it to your own server, wherever you store images on disc space provided by your service provider. Put the URL in the space called "Optional Image URL" in your post. Then you can edit the orignal image and save it again to your own server. The link will the the same and anyone accessing your original post will see your edited image with the "X's" over the chips no longer available.

When you use The Chip Board upload function, it's stored on David's server with a unique file name that is not reused when you do another upload. You could upload your edited image again, but it wouldn't come up with the changes when someone views your original post again.