OK, it's been a busy day on the work bench...
The tender chassis is completed. Since taking the pictures I have given it a better clean, fibre-glass brushed the wheels and as much of the frame as I can get to.
The end axles have no washers (the axles tubes standing 1mm proud of the body giving the required clearance), the centre axle has 0.5mm styrene washers. The water scoop rod that runs along between the back of two of the wheels and the tender body has had a 0.13mm thick clear styrene piece cyano'ed to it to prevent the wheels shorting out to the tender body (the supplied wheels are plastic inserts, so the axles are dead, but the tyres get very close to the scoop rodding).
Next step will be to pop the wheels back off, trim the axles so they fit inside the plastic body, prime and paint the whole thing.
I am very happy with how the tender has come together. I think I will do the tender body next, and then move on to the locomotive after that.