7 1/4 axle shafts needed...

You might have misunderstood what Roy meant when he suggested swapping in a big bolt pattern 7 1/4. In the last years of A bodies....maybe 74-76, the 7 1/4 differentials were switched to 4 1/2 inch bolt pattern on V8 cars. They are a direct bolt in for what is in your car now. Swapping the whole rear end is as easy or easier than swapping axles out of your existing housing. 8 nuts on the U bolts, 2 parking brake cables, 1 brake line, 2 u joint straps.....drag the old one out, put the new one in, and put everything back in place. When I was 16-17 years old, I learned how to do it out of necessity because I was dumb enough to keep knocking the fragile little things out of my 70 Duster! :BangHead: