If the cd is made with an Amigain mind with it's own Disk.info there's little you can do. Like the ICON movex.y. However for the default icons found in your ENV/Env-Archive you can try this.
Go to you Env-ARchive/sys folder. This is where all the default icons are. enlarge the window to the full size of your workbench. In the window one at a move the default cd icons to where you would like them in on the workbench window and snapshot it that position. Move away and place the next, snapshot .....
Now once you insert a cd without a Disk.info the icon will appear on the workbench where you it was snapshot in the folder.