I haven't read it yet. For the 917 I have the next book and enjoyed it a lot: https://www.amazon.co.uk/Porsche-917-Winning-Peter-Morgan/dp/1859606334 On Brian Redman autobiography you learn a lot about the 917 too, like the drivers not wanting to drive it at in the beginnings because they considered it a very dangerous car.
It's crazy how prices go up in this books when the editions finish.