RSPS Devlopment

hello i am working on a rsps that i am planning to make public on our site once it is finished, it is no were near finished but it is getting there. I have made a few 317's and published one of them for use by others. I have only one question. Anyone know how to add a custom 317 code to a 508? for example, custom item Id number from 317 added to a 508, without errors.