> > > A151 - install a switch like the new version to select 2, 3 or 4

steps.

> >
> > center terminal of the switch -> reset input via a standard diode (e.g.
> > 1N4148), cathode (-) on reset socket
> > end terminal 1 of the switch -> CD4053 pin 14 (LED control for I/O 2)
> > end terminal 2 of the switch -> CD4053 pin 15 (LED control for I/O 3)
>
> In addition Peter Grenader describes how to do the mod here:
>
> http://www.buzzclick-music.com/mods.html
>
> Note also that I think pin 14 above should in fact be pin 11.

You are right. Pin 11 instead of pin 14. And the circuit is CD4052, not
CD4053. Maybe I was a bit tired ...

Best wishes
Dieter Doepfer