The most obvious is the neck on the Jazzmaster. The American JM has the decal on top of the finish, where the Japanese/Mexican will have it under the finish. Secondly, the dots on the AVRI and Mexican JM are white on the top of the neck, whereas Japanese are black. Also, the tremelo system's button is flat on a Japanese trem and more rounded like the vintage trems on the AVRI. If you want to get really technical, get a set of metric and American allen wrenches. Mexican and Japanese models will have the bridges with metric sizes, while the American will have the American sized screws. Finally, I have 2 used AVRI Jazzmasters and neither of them came with the mute. That seems to be one of the things people tend to take off first, just as they did on the vintage ones.
