I was about to give up for the day, but got thinking about the undertray. My SP1 tray has been cut to fit an aftermarket one - not nice, but I managed to pick up an SP2 tray with indicators and lights. Unfortunately it needs modifying to fit the SP1 subframe (something I didn't realise when buying). I decided this wasn't an option as I didn't want to wreck it. I got quoted £227 from a couple of Honda dealers for a replacement (one of them told me they couldn't do a discount as it was a painted part!), which I couldn't really stomach, so I went back to an idea I had before I got the SP2 tray.
It just so happens I have a few NC23 spares kicking about, including a complete undertray, The rear end of which wasn't such a bad match widthways, so I decided to create a frankenstein using my old one.
Here's the cut tray

Heres the NC23 one after I hacked part of it off

And here it is after further cutting, fitting, cutting, fitting, cutting etc

Not a perfect match, but not bad and best of all its cost bugger all. I don't think many bar the purists would notice.
Its only tack plastic welded together at the minute, I need to finish the welding so its nice and strong and tidy it all up, make a more secure mount for the tail light and mount the indicators. Chuffed.
Just need a couple of bits of ally welding doing (lh rad and rhs footpeg) then I can move onto the front end - fork seals + head bearings arrived today.
Jobs will be to change the seals obviously, replace the fork springs, refill with 5Wt fork oil, paint the fork bottoms as they're showing a few chips, blast and black paint the 'gold' clipons, clean up the yokes, new headrace bearings etc