The Club Diner was built by the Jerry O’Mahony Dining Car Company and opened on May 22, 1939. Its original owner was Harry H. Schell. The Club Diner is still in business, at 319 S 17th St, Harrisburg, PA. I’ve driven by several times, but never been inside, so I’m unclear whether the current diner is a greatly remodeled O’Mahony Monarch, or if it’s a later replacement. If anyone has interior shots, I’d love to see them.