Do you own a gun or have some big dogs ??
If not, I'd get a half dozen of each.... the bigger the better. That's one nut job. He's even worse than 'you know who '............
Years ago, I had one, where after 9-1/2 hours... yes hours of working, I had to let this guy go for many reasons. He was just a short little thing and he came right up to me... in my face and said almost under his breath.... you think I'm afraid of you. I know you do. Well, I'm not. I'll get you. I'm gonna get you because you think I'm afraid and I'm not. I told him to return my tapes and I really don't care what he thinks or says to me... and then he said.... I'm gonna kick your ass. Not now, but I will.