I am rebuilding the T90A-1 transmission and replacing the clutch from my 1962 M30A1. The transmission had a broken main shaft. After checking the bell housing alignment, I thought it would be a good idea to insert an out input shaft into the pilot bushing/ clutch assembly and check for misalignment. As you can see in the attached video, there is a noticeable "wobble " in the input shaft. What causes this wobble and how do I fix it?