Thanks Hal, Walter,
I just took a good look up there and there's no way I'm hanging even one light from that ceiling, the building is too old, visible cracks where the wire's are attached to the cement ceiling, and I'm not going to add 70 kgs of Kino, I've told them it's not an option.
We're looking at re-bulbing Hal but I'm not sure these fixtures will be compatible, they've got a new version of "energy efficient" compact flourescent bulb in them and the head connectors look smaller than kino bulbs, they're brand new fixtures, I'm contacting the manufacturer now. We might do tests and gel our 6k HMI par (Key Sunlight) accordingly allowing us to use the existing fixtures as they stand.
My measurements put pole cats out of the question.
kevin