Setting XG parameters via SY*** - 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 SY***.

The various data manuals list out the SY*** 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?