AP and PO information Combination

Hi Gurus,

We need to implement a new model in our project

where we need to combine FI and PO information together.

From PO we need the information associated like  IR GR Invoice Amount ...Downpayment Payment

And from AP we need its associated GL related information like cost center profit center..gl account.

We have 0FI_AP_30

For PO which data sources can we implement to get IR GR Downpayment Information.

For both we need the accounting documents information as well.

Thanks and Regards,

Monalisa Mohanty