cropinstop - Sorry, I don't intend to add this feature. The good news is, I added an easy way for you to add anything you want to a PO or a Packing List. Of course, this requires a little manual input. It wouldn't be too hard to implement this with a checkbox to turn it on or off, but to add this on a per supplier basis would require messing around with SQL, and I am really not comfortable doing that. I just don't know enough about SQL. If you don't mind getting your hands dirty, you could always define your subcontractors and then add a simple if statement for them to add this info. Of course, this would hardcode these changes, so it would be difficult to undo. It is an interesting idea though. I'll keep it in mind.
I did a quick but dirty workaround by changing the "city" label to "city state zip" and used old "state" and "zip" fields to store the (one-time) credit card # and account # respectively.

New question - how do I disable sending the packing slip pdf with the email? My dropshippers have their own packing slips and do not want to be bothered with the added paperwork...