Hi Edouard, Yes, it's a good book. I have the same book with a slightly different cover from the same year 2004. I also have another good manual called the Auto Interchange Systems 1950 - 65 General Motors Interchange Manual. The copyright on this manual is 1979.
If any of our members needs information from these books they can send me a PM or post the question and I will look up the information for them. So there is no need to buy the books, you can spend the money on Buick parts..
Tony