I was just about finished and feeling rather proud of myself (Don't scoff: this is all quite a learning experience for someone from a country where labor is cheap. DIY is pretty much unknown in India.) when the mailperson rolled in.
"This ain't gonna work," she said. Turned out the slot was too narrow. But it was the right height and distance from the curb. A few other houses in town have mailboxes with slots. The wife went to the post office last week to inquire if such a mailbox was ok and was told that it was. "Well, I'll talk to my boss and let you know," she said after I ran through this litany of the steps we'd taken, "but I don't like it."
The wife called the postoffice and talked to the postmaster. He's promised to come by on Monday and measure and tell us whether they'll deliver the mail or not.
Hope I measured right. I don't look forward to figuring out how a sledgehammer works.