HELP! I am running a 12/2 with ground new electrical line from my attic to the electrical box. When I open the box and take the cover off, I see all the breakers but the main line comes in from the bottom and up the left side to the top and connects to the box main. I know not to touch those main line and breaker connections, but can I touch the insulated main line wires on the left side of the box. Need to get the new line behind them so I can connect neutral and ground.