Open "DATA.GRF" in GRF Editor
Click Data folder in GRF Editor and typing "num" in search box
select only "idnum" then extract file and rename file, remove "id" from file name.
drag completed rename file and drop back to "DATA" folder and save.
If you can't save "DATA.GRF" or something error when saving, don't forgot windows system need more permission when your game folder in drive "C".
need open GRF Editor with administrator mode (right click GRF Editor, select run as administrator). This mode may you can't drag and drop file to GRF Editor.