I have a 1972 Plymouth 340 Duster, this is has a untouched factory, 8.75 limited slip. Original 3.23 gearing. I am wanting to upgrade to 3.55 or 3.91, most likely 3.55's. I have no performance enhancement knowledge for this project. How much trouble is it to make this rear end a positraction. What must be done? Or what are my options.
