Alignment out will cause high rpm vibration. Sounds like clutch chatter to me. I'd check the surfaces if your clutch and pressure plate. Also the disc needs to have good springs and attached to the steel in a way that it has some space in between the two disc. I had a racing disc with solid backing on the material and it would shake terribly. I think it's called the marcell that it's attached to and it is cupped so it acts like a spring or cushion. My best guess.