If you're looking at your diff cover, thinking this is going to be a messy pain in the butt, look for a small metal tag atached to the cover with the cover bolts. Take a brass toothbrush, or something similar, and get the #'s off it. the tag should give you the model amd gear ratio. Some dana models give the ring and pinion count, but on smaller dana models you shouldn't have to do the math

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84 CJ-7, Homebrew FSA conversion, D-44 D-70, Cage, Crazy Gears, Big Meat,Propane, Custom dents(entire body)