Your post indicates 2 things,
1. You are not an electrician.
2 You are not qualified to charge people money for this.
You don't know enough to even use the correct terminology.
Tell the client, you're sorry, but that you cannot do this job because you do no have the required skill set. And rather then cause his house to burn down or someone get electrocuted, he should hire someone qualified to work on the electric.
"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."
B. Franklin 1759