Lets see, capacitors and coils affects the resistance in a circuit. The resistance varys over different frequencys. So the eq has coil+cap connection to get a frequency band. The 5 controls are there so that you can vary how much of the frequency band will get through to the next stage.
The eq-controls, you posted a picture. Isn't that your picture..? The 5 controls seems to be mounted already.
By the way. I like your spirit - jump in the deep end! Just don't underestimate the voltages you're going to mess around with.
Edit. I just had an other look on your picture. The switch is to stop the signal to ground dump. In other words, a switch that works as an on/off to the eq.