PTK, I took the case and extension cord back to the rental place. I asked the owner what the worst case scenario would be, and he said not to worry about it. He was 100% certain it would work again. That was awfully generous of him, considering the circumstances.
So, now it's on to a 60 pound jackhammer. Then putting in a new post. Then putting the last panels and the gate back together. Then power-washing the whole fence before painting it. I should be done in about a month, and out about $1200 now.
I should have just torn it down. It's not like I sunbathe or anything.