Request is to allow custom fields to be modified from contacts to text

Originally, I had selected to create a contact field under thinking that I would be able to add contact names, but the field automatically linked the names associated to the names that have been registered to under people/contacts. So, I need to modify the custom field from "contacts" to " "text", but that's not possible. Request is to allow the user to modify the custom field type rathe than having to delete it.