I second all the people who say "never convert (even non-destructively)
an instrument to play MIDI".  However, I will do it to my Roenisch
pianola some day (non-destructively), because I need it for trying
out some arrangement things (which will then be punched on paper).

I would never demonstrate this modification to anyone (except to
other arrangers); and maybe one day I'll know enough about the
instrument to arrange without trying out things via MIDI. But right
now, the "development cycle" think -> arrange -> have it punched ->
mail -> try it -> think ... is too long and too expensive for me
without MIDI.

Regards

Harald M. Mueller