I also took the chance to figure out the DB9 port on the back for external clock control switches. The game clock can be run from the front panel, but you have to have a wired remote to run a shot clock. I discovered there's also an option to run the game clock this way, too.
A plain text version of my writeup is available, as well as a PDF.
(Yes, this is utterly useless and uninteresting to most of you, but now the search engines will find it for people who might need this.)