Todd... other than the flanges...the most obvious is the hole size in the end of the crank....71 minus the bushing is just over one inch and the 72 and newer is about 1.8 inches to fit the button on the TF..TC. Jim _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list