Can the pinion angle change from one car to another ? We took the 8 3/4 rear out of my dads 67 gtx & put it in his 62 polara. We drove the gtx & it ran fine no vibrations. Now in the 62 polara there is a vibration. Got the drive shaft balanced. Took the wheels off. Checked every thing. I was told it might be the pinion angle.
Also, you might check those axles in the 62, there is a year or two where the 8.75 had axles that were longer inside the carrier than the later 8.75s. I don't recall the exact year though
