Will the rear axle fit?

Ok, well my father and I have talked it over, and we have decided to just stick with the 8 and 1/4 and put some 3.23 or 3.55s in it. We also talked about the posi, and from his research, there isn't that large of a benefit from a posi. Thanks guys!

That depends on what you're going to do with the car. One of the first things I did with my duster was put posi in it. What are your plans for it? Ever plan to do a burnout?