Linking SNP PPM to desired ECC production version

Hi

We have a need where we manually create SNP PPMs and so the APO and ECC have no connection in terms of the PPM or production version.

I have two SNP PPM1, PPM2 in APO and I have two production versions in SAP ECC, VA and VB.

The requirement is to some how maintain a table in APO where we can choose to map the SNP PPM to ECC production version.

something like

SNP PPM1 and PPM2 both need to refer to version VB so that an SNP planned order pushed into ECC would automatically pick up production version VB.

Appreciate if any one can throw some light on how we can create a user maintained table or Z transaction  in APO to achieve this.