Any suggestions on how to mount this clock using only a single mounting point?
It has a pendulum so it needs to be relatively level. I tried to run a piece of wire between the holes hoping to fish a piece of string or something to create a triangle for mounting but no such luck.
Well, with wire, you can thread it through the holes and then wrap it around itself.
But here's an alternative. Get a couple of pictures hooks, something like this . Tie one onto each end of a piece of string or wire. Put the hooks into the holes on your clock, then hang out over the thing on the wall.