Its not in the carb mounting, the difference is the intake boot and the thickness of it when it comes through the carb box. The one for that style that Randy has offered you is thinner. Randy is right, its in the thickness of the intake boot mounting hole in the carbboxes. If you switch intake boots with the wrong carb box you will get an air leak. The number of the early style carb box is 0100, the older is 0102, which to my knowledge is not written on the carb box. All you've got to do is remove your carb box and put this one on. Or get your dealer to order you the right boot. I'd personally switch carb boxes but its up to you.