Add Custom EDI ID Types

Has anyone done this?
I want to create a New EDI ID type called AS2Name to be used for EDIINT purposes. The ID in the payload is not always the ID used in EDIINT wrapper and this varies by partner. I could use one of the User Define ID types but they may be in use for other purposes already.
Now here’s what I’ve found so far:

  1. Update the drop down in the WmEDIforTN\pub\addEDIIDType.dsp which when runs should update the IDType table.
  2. I don’t need to worry about wm.b2b.editn:ediPartnerIDToTNPartnerID service as my ID will never be used in the payload.

Question. Where would I assign the value for the new ID, ie. 80.

Has anyone done anything like this before? Am I missing anything?
TIA