The inner skirt of the fender is shaped different, they mount different, and they will not readly interchange between models. But as William said, some people have switched them between models, but normally the fit leaves a lot to be desired. The skirt of the Original fenders is not deep enough and does not have the lip/flange along the bottom to fasten the axle straps that are used on the 70/100. If you use the Original mounting pan, the fenders sit too high, unless they are modified.