RockAuto can be wrong. The 1 1/8" rotors were only offered late 76-78 CJ5 and CJ7 with the "6 hole" caliper brackets. Both of the later style knuckle mounted caliper brackets "2 bolt" used the 7/8" rotors. Don't let the internet fool you, it isn't always correct. Just wanted to clarify it for someone using later stock Dana 30 Jeep knuckles to do a disc swap on an intermediate Dana 30.