Trying to help a friend with leakage from his rear axle bearings. Nobody seems to have the o-ring that fits in the groove of the O.D. of the outer bearing race. The I.D. of the o-ring is about 3+ inches, and the cross sectional diameter is about 0.075". I've tried NAPA, O'Reilly, Rock Auto, honestjohn.com, cadillacking.com, mcveys.com, fusick.com, allcads.com, antiquecadillacparts.com, arizonavintageparts.com, and caddydaddy.com. Graingers and McMaster-Carr have extensive o-ring assortments, but I need to know the exact nominal measurements and the '57 Cadillac shop manual does not give that information. Where can I get that O-ring or dimensional information?