The Subject says it all, really. After a bit of a clean up, I mounted the key on a steel base I had drilled, tapped and painted. By some fluke the holes lined up so I was able to screw the thing down. I'm not happy with the brass machine screws I used, which were dome head. I'm on the look out now for similar size brass raised head screws, which I think will have a less intrusive look. Total weight is a smidgen over 1kilo.
Vic / off to burnish the deckheads.....