Now when you have the machine square and secure on the table, it ís time to adjust the eccentric spacers on the gantry and the Y bar assembly. Adjust the spacers so, that there is no slack but the movement is still free. The easy way to do this is to loosen the spacer so that the wheel does not turn when you move the ganry or T bar. Slowly tighten the spacer, until it is not easy to turn the wheel without moving the machine. Do this to all eccentric spacers.
Re-check that the movement is free and no spacer got too tight.