These parts are just like the stock 73-77 Bronco parts no longer available from Ford. This kit consists of a new main shaft, tailhousing, bearing retainer, seal and hardware. The installation is easy since the cross-member bolts directly to the new tail section. Your 3-speed drive sleeve might need shortened to use with the new output shaft. No driveshaft modifications are necessary. An aftermarket shifter or C4 Auto shifter from a Mustang, Pinto or 73-77 Bronco will be needed