May help some other out there.
I found the oil catch tank drain screw tricky to get to as it sat behind the left side tool box (and of course underneath).
I had to mod that!
I fitted a tube into the original screw hole and then fitted a clear plastic pipe to it. I fitted a valve inside the 'tool box'. I removed a spare screw that just seemed to fill a hole in the rear of the box. I passed the plastic pipe inside via this hole and then fitted it to the valve. The valve is a screw down fish tank type one and I 'trapped' the lower edge of it under the brake light switch cover. I added a further piece of plastic tube and coiled it up inside for draining when required.
Does it work?
Very well I'm pleased to say. Much easier and cleaner than before.
PS Can anyone tell me what that 'spare' blue triple connector plug (with the orange, black and a white wire) is used for in the left side tool box shown here?