that's a typo and should read '71-76'. check the other sticky rear end info thread for interchange information with the 8 1/2" ring gear pumpkin. you probably need to verify your rear end size as well. my 76 electra has an 8 7/8" in it. you can't get aftermarket ring and pinion sets for either the 9 3/8s or 8 7/8s.