Operator Presence Switch Twist Mount Adapter

It seems that most aftermarket tractor seats use this twist-mount operator presence switch. My old seat used a direct mount, so this is an adapter so that I can use the switch (which seems to be a somewhat universal design) with the new seat.

The pressure-plate is free and is aligned with some 8mm posts. I think this sufficient, but I'm sure it could be more intricately modeled such that the plate snaps in and is retained.