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.
Hmm. Is the mounting plate with the screw holes removable? If you could flip it so the notch is facing down and drill a hole in the middle that might work.
How heavy is this clock?
It is not removable, it is all part of the "clock" assembly.
It is not heavy at all.
That's unfortunate, maybe as someone else said you can make some sort of "adaptor" using wood? All the best mate