You still should use one of the Insert Page Number or Insert Field options and not attempt the manual entry.
"From the Insert menu, choose Page Numbers. Select a positiona and alignment for the page number. To change the number format, choose the Format button in the Page Numbers dialog box. When you finish, choose the OK button." - MS Word User's Guide for V.6 1994

Creating codes is practically impossible. You are always best to edit after any Auto Text creation. These haven't changed much if at all from then to today.