700 R4 Transmission

How much vertical and lateral movement is considered "normal" pertaining to the drive shaft spline yoke within the transmission tailshaft bushing?

The tranny was rebuilt with all new bushings and components & wondering if possibly the wrong bushing could be in place or one with a larger bore size than GM specs.

I can move the tail shaft up and down with the palm of my hand with very little effort and can actually feel a "bump" while doing this. The trans shop says "normal" but how can i verify that is correct or just BS

I have been trying to chase vibration issues and the entire drive train has been rebuilt and balanced from the harmonic balancer to the rear lug nuts
and i still have the vibration. The tailshaft area is the only area i can find that has any movement of this sort and was wondering if that "bump" i feel when moving the tail shaft could possibly be the source of the vibration

Shouldn't move much, if at all. Take it to a trans shop other than the one that did the rebuild and see what they think. If they say it is bad, get it in writing and take it back to the rebuilder and demand that they fix it.