Custom menu items in a copied workbook

[64.5 Mustang]

I copied a workbook with a menu bar that has macros assigned to the custom
menu items. When I open the new workbook and click on the custom menu item,
it runs the macro from the original workbook. Is there a way I can code the
menu item in the new workbook to choose the current workbook macro? I could
code it to run when the workbook is opened, if this is possible?

Thanks in advance for your help,
Diane