11-41 would be a 3.73:1 ratio. That's not one that would have been available in the HO-72 rear axle. Chances are what he's got is a Dana/Spicer style rear end from a GMC truck that does not have a removable carrier. Unless you're willing to swap the whole housing, that one's not going to do you much good. I've got a Dana Type 60 3/4 ton limited slip rear axle under a 59 Suburban, and I believe I installed 3.73 gears when I built it up around 40 years ago. I do recall using a GMC housing, Ford gears, and a Dodge pinion flange on that buildup!
Jerry

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