Unless you are a certified electrician, I would suggest you hire one. You will need to upgrade the wiring through out the house. Not just at the circuit breaker box. We lived in Philadelphia, Pennsylvania when we upgraded our house and the city required a certified electrician to meet code standards. In the event of a house fire your insurance will cover it as long as it is not a do it yourself job. If you miss something and have a fire you will be out of luck. I live in Florida now and there are still codes that have to be met.