A bit of progress today: I've identified the tin work as all being the correct stuff - mighty puzzled at first as some was too large, until I realised that the fellow I got it from had adjusted the height to suit his new Mori Seiki lathe which had a spindle 60mm lower than mine! It screws up and down on jacks inside the framework.
Turns out the plonker had seen the bar feeder had a 20 pin industrial socket the same as his new lathe. Put them together,but didn't bother to check the pinout, which was different, blew out the psu on the bar feeder and caused £3K of damage to the Mori

Anyway - progress: A nice man in Germany has emailed me some technical info on the unit: Not exactly the same physical layout in the electrical tray, but seems to be the same actual circuitry: