This is now on the road and in use. It came apart as much as was needed:
Brakes - all three calipers were stripped and cleaned and new parts ordered as necessary, rear disk, stainless pistons, seals, rubbers, pins, braided lines, fluid and master cylinder kit were all carefully re-assembled, they are now very sold at the levers and stop the bike beautifully.
Suspension - Ohlins shocks replaced the tired Hagons, I have collected a pair of fork legs and new bushes and seals, I shall send the legs for re-finishing any day now and, once returned, refresh the forks.
Wheels and tyres - new paint went on the wheels along with new bearings and the tyres pictured above, it rolls very smoothly.
Bodywork - re-painted in Honda Italian red. Both side panels were broken at their top mounts as they tend to be so a couple of Chinese panels were given to the paint man with tank, tail and mudguard.
Mechanics - carbs were removed, float valves, jets and gaskets were replaced as were both throttle cables as the shut cable that came on the bike was snapped. The choke cable was frayed at the lever end so this was renewed too. All service items were replaced as were the fibre clutch plates. It starts on the button, purrs like a kitten and goes like it should, all very satisfying.
Controls - the flash button didn't work and both switch housings had their locating pins filed smooth to fit the Renthal bars when the bike came. Ebay helped with good housings from a CB750 (the same as NC31) and some working NC31 inners so I sat and made a good pair out of those collected. A copy chrome handlebar needed drilling to accept the switch housings in their correct positions and, after much work for many hours, it was all re-assembled and works well.
Other bits and bobs - a plastic copy headlight went on. It's cheap and flimsy and I don't like it much but it's not accident damaged like the one the bike came with. All four indicators were replaced, the grab rails were powder coated, a Renthal rear sprocket went on, various fasteners were replaced (or fitted, some were missing!) and everything was thoroughly cleaned and lubricated.
There's a few areas that I would like to improve - the clocks seem to over read and the temperature gauge doesn't move, I suspect that they are Chinese, I would like to find a genuine set. The seat was recovered, the trimmer did an excellent job (as he always does) but it had previously been cut away to make it lower and the new shape isn't as comfortable as I remember so an untouched seat foam would be great to find.