Hi Steve,
I've been enjoying this thread - fine modelling and great loco pictures - and I've been hoping you might turn up one of 5961 Toynbee Hall. I am modelling this loco in 4mm, having taken over a part completed scratchbuild from a friend.
Toynbee Hall was outshopped from Swindon with a Hawksworth 4000 gallon tender in sparkling condition June 1962 and returned to Canton. I am not sure how much engine cleaning was being done at Canton by that time, as a couple of pictures I do have seem to suggest it got grubby fairly quickly.
Ian