MK113. Siren, switching of sounds

Velleman Kit MK113

I have downloaded the PDF file. I only need three sounds. Police, Fire, Ambulance. Is there any way I can modify the circuit to be able to select Police with a single on/off switch? I want to use remote on/off switches to select Police or Fire or Ambulance individually. I have a switch from a failed original circuit of another make of PCB that will restrict me to selecting Police or Fire or Ambulance

Regards, Mr G B Taylor

Due to the nature of the applied IC, such operation is not possible.