The first order of business was to locate a suitable 8 3⁄4-inch rear for our conversion. Being highly sought after, A-Body 8 3⁄4 rearends tend to be pricey at the swaps, and are always thin at the boneyards. Looking for the low buck score, we checked the pickings at our local wreckers and found an early Valiant with an 8 3⁄4-inch perched on its springs. Pre-'65 8 3⁄4-inch rears used the old style tapered output axle shaft, with a separate hub secured by a large nut, as opposed to the modern flanged output shafts used from '65-and-up. The rear had obviously been sitting there for quite some time, overlooked by all takers because of the oddball tapered shaft and hub output. Since we knew we'd have to change the shafts and brakes anyway, we stripped out the stock old-style shafts and low-performance differential. We brought home the bare housing at the bargain basement price of $19. These old tapered-shaft rears can be to the modern flanged output axles simply by using the corresponding late-type axle shaft seals and bolting in the modern axle shafts. The housings themselves are essentially the same.
Although any of the above discussed approaches to converting the bolt pattern would get the job done, when we were ready for the job of changing over our 8 3⁄4-inch, we picked up the phone and ordered a set of custom axle shafts from Moser Engineering. The Moser shafts are 4340 steel forgings, ensuring they'd be up to any dragstrip punishment we would subject them to. Since they are a custom axle, Moser can build the shafts to whatever specification is required. Want to keep the original narrow A-Body brakes while moving to a beefier large-flange shaft? Just order the custom shafts with the stock backspacing (you'll still have to drill the drums to match). Our choice was to have the shafts built with the wider, large-car backspacing, which allows us to run the much more common and beefier big-car brakes (we went with mondo 11x2 1⁄2-inch units). For those who want to take either of the bucks-down paths to the changeover, Moser can redrill the stock A-Body 8 3⁄4-inch shafts, or perform the cut and re-spline job on a suitable set of used replacement axle shafts.
With the new axle shafts, our conversion was a true bolt-on task with no custom machining or one off components. The only trick was to locate a set of parking brake cables of the correct length to match our A-Body chassis. Some boneyard digging and measuring, and we were able to locate cables to fit our application (taken from a '76 Dart with 11x2-inch brakes). The cables must come from a braking system of the same diameter (but not necessarily the width) as the drums you are going to run, since the length at the apply end must match the diameter of the drums (e.g. cables from 10-inch brakes if running 10s or from 11-inch brakes if running 11s). With all of the components in hand and a new high performance gear set (see "Pig Hunt," Mopar Muscle, July '99), putting together our modified A-Body 8 3⁄4-inch was reduced to a simple nuts-and-bolts task. The photo captions outline the basic wrenchwork.