Hi Thomas, I have a 140 FHC 1956 which is awaiting restoration and which I hope to start when I finish my two Healey's I am presently doing, fingers crossed no more earthquakes, and maybe a blessing from above or somewhere I will start it early next year.
Anyway a couple of months ago I purchased a fantastic book "Jaguar XK140 Explored by Bernard Viart" published by PJ Publishing Ltd, Barton on Sea Hampshire UK. I think it is available from paulskilleterbooks.com, it is a MUST HAVE for an XK140 restorer/owner, it gives you all the demensions you are looking for.