Existing form attachments from OM to a custom form

 Hello all,
We have attachments enabled for Order Management SO (OEXOEORD) and everything is fine.  What we would like to do is see those same attachments showing in OM, in a custom form(xxprk_shipments).  Every document I can find on enabling attachments assumes you want new attachments.  I want to view/update/delete in both OM and the custom form, the same attachments.

Thank you for your help.
Kkerig