I made up a temporary gearbox mount to match the temporary motor mount I made a couple of weeks ago. It has several problems, notably it doesn't have any rubber to absorb shocks, the box section bolted to the gearbox doesn't have anything to stop the bolts crushing it, and that box section could be significantly strengthened by capping the ends. Really I should have used a flat plate against the gearbox.
While it's not a great mount, it allows me to install the front subframe and flesh out how I'm going to support the motor controller on top of it all. This is significant because it's likely the final mounts will serve both purposes.