No, I didn't PM him - other people might also be interested.
I have ordered the CD of the book and will publish a list of contents once I have it.
Tony
I'm interested. It's just that I suspect Centurion made those drawings up based on information in (I think) Devil's Chariots and/or A New Excalibur. ie, I think he made them up, even though they are based on 'facts'. He may have made other drawings at the time; 1st or 3rd angle projections and so on. So it may be worth trying to contact him.
It's possible he had a copy of the tank schematics book I mention above, and that is the only other possibility (in terms of books that may mention "drawing board tanks") I can think of, so it will be interesting to hear if these tanks are included on your CD.
I've seen a couple of photos (a year or so back) on the IWM website of a mock-up which seems to fit Centurion's drawing for a Mk.V***; certainly there was a mock-up featuring an enlarged driver's cab, different sponsons, and a hull extension that protruded above the slope of the track return at the back, whilst staying level with the roof.
However, if that is indeed the design Centurion was depicting, I think he may have misidentified it, because my understanding is that said mock-up represented the ORIGINAL Mk.V design - the all-new design that was abandoned in favour of a less radical change based on the existing hull, ie the production Mk V.
The photos depict the mock-up in the same location that the Mark VI mock-up was photographed in mid 1917, and if memory serves, the other mock-up was pictured about the same time - a suitable timeframe for an early design of Mk.V, but not for a V***.