In this first picture we see John and Paul sitting side by side with their heads at about the same distance from the camera. You can already notice how small and round Paul's head is in comparison to John's. If you took John's face and superimposed it on top of Paul's, John's eyes would land somewhere past Paul's eyebrows. Also notice that John is a little broader than Paul. Now, it is known that John, Paul, and George were all approximately the same height, about 5'11". Look at the wax figures of the Beatles on the Sgt. Pepper album cover for an example of this (Also, compare these figures with the "real" Beatles in the same photograph). 
     Here is another quick example. Paul's head almost looks like a little kid's next to John's: 

     We can already tell that something fishy is going on. Look at how small Paul's head looks on those shoulders. And speaking of shoulders, this guy is at least two inches taller than John, even with that beanie little head. If you look through the other photos in the booklet you will notice that they are all wearing the same kind of shoes, so clearly the original man in this photograph was taller than John Lennon. 
 

     HIS HEAD GROWS!!!! Not only does his head significantly change size, shape, and particularly height, but the addition of the real head places him between 2 to 3inches higher than John. "Paul's" (emphasis on those quotation marks) nose is now at the same height as John's eyes. And now, with the real head, their faces are just about the same length, whereas, before, John's face was clearly longer than Paul's.  
     And this man is significantly broader than John Lennon; about as much broader than John as John is compared to the real Paul above. And again note that even though the photos are now in proper perspective, you can still clearly see that the real Paul's left ear hangs out past the other man's head. Clearly this cannot be the same individual. So what about this difference in height?