I think the issue is the ratio. I believe 4.56 and 5.13 used a different carrier than the 4.10 and higher. Of course, the earlier ones only had the lower ratios. Since the pinion on the low geared ones is smaller, either the ring gear must be thicker or the carrier mounting flange must be closer to the pinion. A visual check should tell you if you have everything apart and can compare.
