The Ford front differential is a reverse cut, not a reverse rotation. Some truck manufacturers use/d a reverse rotation, as did old Fords. However the reverse rotation is weaker than a reverse cut as the pressure is on the weak side of the gear. Ford had Dana design a special differential to make it stronger which is the reverse cut. The reverse cut differential also provides a shallower angle for the drive shaft. They are often confused, but the design is different. A reverse rotation differential is a rear differential mounted on the front with the necessary stearing hardware added.
Front and rear gears have to match in ratio, otherwise the wheels will turn at different rates. ex. 3.73 tell you how many turns of the drive shaft for one turn of the wheel. So you can see that a miss match will make for an interesting ride.
Good luck,
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