Add Shipping Notes to Orders

Client has 'broker notes' that must go on all sales order documents.  These cover broker name, contact name, phone number, fax number, and other shipping information.

We are using Delivery Instructions, which are setup at the Ship To Customer level for other similar notes.  However, the broker notes are larger than the 2 fields available, which both have 30 characters length.  The only other alternative I can think of is Print Messages, and this would require us to setup each message in a separate application, name it, and then attach it to the Customer Master.  Another alternative would be Sales Order Header (or Detail) attachments, but these would have to be added to each order separately.