The factory Rave discs are all available on line, if you search the forums, pwople have put up links to them.
For a Hard-Copy of something to stick in the car, the Factory 'Repair Over-Haul Manuals' are just about as definative and comp[rehensive as you can get; each model has its own ROM, priced around £20 from Paddocs or Craddocks and most good parts emptoiums; and there is one specifically for the Rover V8 engine, which is pretty darn good.
Again, there are pdf versions of a lot of these 'out there' on the web, yo down-load.... but tricky to carry in the car.