Just so we are clear on what you are asking. The 57 58 59 Ford rear axle housing are what you need to put under your 54 55 56 Ford car. They were all 28 spline small bearing housing. They will except either an 8 3/4 or 9 inch pumpkin. So is that the question? PetePS the 58 has a smoother rear cover (in my opinion,) no dimple.