Some ? about my 8 3/4

First off what is the length of the housing, flange to flange? Just curious. If it's not longer than an early B rear I would just move the perches in and bolt it in. I have a B rear in my Dart Sport same body style as your Duster and it works just fine. Could be a huge savings for you.

Unless you have a bunch of money to spend that is. After putting a suregrip with 3.55's, new brakes, hardware and lines, I have around 600 bucks in mine.