A fundamental part of any muscle car is a nice, strong rearend fitted with a limited slip or Posi unit. What good is it to make gobs of horsepower if you can only do one wheel burnouts or if the diff grenades the first time you put the spurs to your new engine? Plus, the best way to transfer that power to the ground is through two tires, not one. Lately the trend has been to ditch the factory rears for a 9-inch, but not everyone wants Ford-style parts on their Chevy. So for all the purists out there, we are going to rebuild a 12-bolt with stronger than stock parts and add a new limited slip differential.