I have g&l Legacy special which is about 10 years old (3 neck bolt on

Recently, my bass knob has stopped working, so i opened up the pickguard to see what is going on.
I have found a couple of things that interests me.
1. Ground brass plate which was under the electronic parts. All the wires were going through the plate
2. Pots and the ground brass plate and back of those dual-pickups were coated with some sort of wax on it. I tried scratch them out. and it easily came off
I will be replacing the bass pot to new one, but at the same time, i am planning to change all PVC coated wires to vintage cloth-coated wires as well.
Here are my questions
1. what is the function of grond brass plate? can i solder my wires without passing through the plate? if i do, would it affect my guitar tone?
2. what is the function of those wax coating on pots, ground plate and behind the pickups? i took out the plate and brushed it cleanly under water so it does not have any wax coating anymore. Should i replace those was coating back on the plate? also, the new pot does not have any wax coating on it, should i place some wax coating on it as well?
3. To replace the wax coating, what should i do? Is there some sort of specialised wax spray that covers the electronic parts with thin layer of wax?