Abstract: A centering tool assembly helps centrally position a casing in a tubing using a baseplate, actuator, support tube, power source, and reaction studs. The baseplate is positioned on an outside edge of the tubing. The actuator is either preinstalled on the baseplate or installed after positioning on the tubing's outside edge. The support tube vertically adjusts the actuator. The power source activates the actuator which provides a force against the casing, moving the casing into the central position. Reaction studs or counteracting members help stabilize the centering tool assembly during this positioning. The centering tool assembly may be used to either pull or push the casing into the desired position. Additionally, a method for centering a casing into a central or desired position in a tubing involves placing a baseplate on the edge of the casing. An actuator is installed on the baseplate and vertically adjusted via a support tube.