For those in search of a Grand National / Hurst 8.5 rear axle, here is the reckoning when you find one of the 25-year old refugees. Examine the following picture and decide whether a Ford 9" might be a better choice. Here are $960 in parts to upgrade to a 30-spline axle with 3.73s. I picked up the Auburn posi on Craigslist for $250, so the 30-spline axles to match are only a $100 upgrade. Also needs outer axle bearings and seals , ~$45. Oh, and add $150 in labor for the ring and pinion set-up. I picked up the axle for $800 shipped to my door - one-legger with 3.42s, 80K miles.
