The dishwasher has been successfully installed! It took 3 trips to Lowe's, an electrical shock, a banged thumb, and a few tries - but DH did it. He believed he could do it, and he did in spite of my doubt. He continues to amaze me with his persistance and skills.
I'm glad we have the new dishwasher - first of all, it's white, which looks better in our all-white kitchen. And it is much more energy and water efficient than the old one. I can already tell the capacity is much greater, and one of the cups that I had hand-washed came out cleaner than when it went it. So I guess it works.