Oh dear, I've really gone and done it now... I've bought 'GWR Switch and Crossing Practice' published by the GWR Study Group.
Any ideas I had about not worrying too much about the finer details and concentating on the overall look and feel of my model have gone right out the window - along with, I have to confess, any street cred I might have had left!!! Hands up, this is a truly dull book in any 'normal' person's view, but I'm afraid to say I'm finding it quite fascinating! Sad, I know!
Anyway, for anyone equally sad who isn't already aware of its existence, you can find out more about the book here. I managed to order mine online via Biblio.