In marketpress how do I get the order details in the confirmation case of _mp_cart_payment in your t

I am trying to add some post order processing to push the order into a manufacturing system. The system is only using paypal chained payments. The calls to move the order into the other system need to happen after the order has been finalized with paypal, which is why I am looking at the _mp_cart_payment function.

In the end my questions are:
1) Is there a better place to do this?
2) How do you retrieve the order details(and shipping) from within the confirmation case since there doesn't appear to be a fielded order id in any of the arrays. I can see it inside of the nvpstr element and parsing that string to get it has crossed my mind but it seems like there should be a simpler option.

Thank you.