An Old Book In New Cover
This is a barely updated book published as a Peterson's title in the late 70s, and while the basics (as applied to RWD cars with front engines) haven't changed, the laws have and so have the reasons for swapping in most cases. The most popular subjects for engine swaps today are four wheel drive vehicles, particularly outside the USA where no off-road vehicle is taken seriously without a diesel engine.
A new edition of this book could be very good, especially if written with non-US readers as well as Americans in mind.