Mike,
Thank you very much for posting these drawings. I have only a passing interest in the LNER and am very unlikely to model a Gresley carriage but I do appreciate good draughtsmanship. It is a joy to view the drawings and I hope modellers of the same appreciate what you have made accessible.
As modellers original drawings are essential for our craft of reproducing the past in miniature. There are hundreds of drawing held by individuals and institutions which are not always available for study. Most, if not all, have no comercial value but to modellers they are invaluable.
Ian.