A modern Dana 60 front axle comes stuffed with much stronger 1.5-inch-diameter, 35-spline axleshafts (center), which can safely handle 37-to-44-inch tires ... 1550-sized 'shafts and U-joints ...

Unless you want to carry two spare tires, you will need a pair of after-market axle shafts for your A-Body axle, but with flanges sized for the larger 4 1/2-inch lug circle. Custom axle shafts of ...