Trans vibration or no?

I think to check the balancer, you need to remove the number one plug. Put in a piston stop. Rotate clockwise till it stops.mark balancer. Rotate counterclockwise until it stops. Mark balancer. Measure between the two marks, finding the center. Mark this. This is actual tdc. If it doesn't line up with the factory mark, the balancer is spun.
I had a torque convertor that wasn't balanced properly. Caused a vibration like you describe.