PI graphical mapping: target node based on two source nodes

Hello experts,

I have an incoming structure like this:

the target structure is:

Where (number of ITEM) = (number of SPLIT) X (number of LINEITEM)

EMAIL = SPLIT[Owner]

PARTN_ROLE = Index of SPLIT

ITM_NUMBER = LINEITEM[LineNumber]

How do I do this using graphical mapping and/or UDFs?

Any help is appreciated.

Thanks!