Hello,
you can modify that by going to the Graitec Manager, under table editor, extend AstorDetails, find the title DetailFilenameSelector. Once you click on that, you will have the content of that file to the right of the window, in from the column "Prefix" change all the (03) to (01). Do an update defaults and update your details, sometimes you need to recreate the detail sheets in order to see the modifications.
thank you.