Sounds nasty, hope you get better soon. I have an old Merry Tiller rotavator but as I have no interest in gardening, I suspect I am fairly safe. As I sometimes say, the only time I have green fingers is when I have been painting parts...
Son of Sherman will give you everything you need and there are plenty of pics on the net of Commonwealth Sherman III. The few books on British use tend to miscaption many of the photos so care is needed.
I'm not sure I'm the man to write a book, I think it's much harder than it looks!