What year/model car is this for? The differentials both have the same ratio if your current trans has a 3.29 gear, the HD trans changes the ratio in the drive/driven sprockets to accomplish the 2.93 overall ratio and there is nothing special needed tuning wise to swap from one diff to the other. You will need an HD diff, diff housing, bearing and spacer for end of diff, HD output shaft as it is longer, and an HD passanger side axle. I have all the parts for the trans end of it unless you have something lined up already and for an axle you can either ask Ed Morad or buy a new one as they have recently been available in the aftermarket world as brand new-no core charge pieces for around $100
