Setting XG parameters via SYSEX - Panel voice part number

[DerekA]

I know I can send a control change (CC) message to a specific MIDI channel, and use the MIDI setup page to say which MIDI channel each panel part (L, R1 etc.) is listening on. I use this with the Korg NanoKontrol as a kind of basic live control.

Voices also have a number of XG parameters (e.g. initial touch depth) which can't be changed via CC messages, but can be changed via SYSEX.

The various data manuals list out the SYSEX messages in the 'MIDI Parameter Change Table (MULTI PART)' section. One of the values on the message ('nn') is the 'part number'. I can't find any details to say what the 'part number' should be for L, R1, R2 etc.

Anybody know?