Having issues tracing down a vibration at hi speeds. 6 speed 3:73 gears. Driveshaft pulled and checked at shop to check balance, guys said perfect. Rear end gone through all new bearings still has the vibration. Everything tight bushing good transmission and engine mounts all good and tight as well. I've decided it's pinion angle or maybe a transmission bearing causing the vibration. So any thoughts or have your accurate pinion angle degree? Thanks