Blueprint:
They call this a 'General Arrangement Drawing', and when I (publisher, Paper Trade) did the preparatory research before designer Cor van Haasteren started work I searched high and low for more drawings. This was all I could find - it is for sale at
The 'Sir Nigel Gresley' Locomotive Trust Ltd, the private foundation which owns, runs and maintains this locomotive.
The only other information we had was lots of pictures on Google (though I never came across the tender pictures in Erik's latest message), and pictures I was able to take of the engine in the maintenance yard in August 2015.
Sincere compliments to Erik for his work on the brakes rigging!