On the wikipedia page for the Ca.60 it says:
The two nacelles also housed a cockpit for one flight engineer each, who controlled the power output of the engines in response to the orders given by the pilots by means of a complex system of lights and indicators located on electrical panels.
I would like to know more details of how this system worked, such as what the function of the switches were, and what was communicated with the lights.
If nobody knows how this particular system worked, maybe we can infer how this worked from similar systems used in the past, if any existed?
There is a picture of the remains of this panel on the wiki page. Here is another picture that I found. Any ideas?