Purchase Requisition collaboration for SNC

Hi Experts,

We are in the process of configuring SNC, to share Purchase Requisition Information with Supplier. We found that there are no standard processes defined in SNC for Purchase Req collaboration. We can use the IDOC PREQCR01 to send PReq to XI, but which XML message to use to send it to SNC. Probably we have to define a new XML message for the same. Can you please help how to define a new XML message type in SNC for Purchase Requisition. Or is there some alternate way by using existing message types.

Also we need to change UI in SNC to display Purchase Requisition and processing the same for PReq confirmation.

Request you to please help out on these issues.

Regards,

Shiv.