There are factors to consider other than gear ratio. Sure grip ?, Clutch or cone type ?, Original A-body housings or modified to fit ?, Still straight or need straightened and back braced ?.
redfish, can you elaborate on this? I'm a differential dunce and I've just picked up an 8 3/4 over here in Australia (they are extremely rare here), 489 carrier, cone type sure grip, 3.23 gears. The axles and housings will need to be shortened to fit my 68 cuda. Im running tall tires (275/60 x 15).
Why would factors such as sure grip, type of sure grip, and whether or not it is an original Abody housing influence choice of gears, or have I misinterpreted what you are saying?