A method for aligning a centerline of a motor shaft in a direct drive fan assembly, the direct drive fan assembly includes a hub, a fan and two motor supports that each include a respective notch, the method comprising: selecting a motor from among a plurality of motors; matching a motor plate from among a plurality of motor plates to the motor, the matched motor plate is based on the selected motor, creating, from the selected motor and the matching motor plate, a motor-plate assembly that has a resulting height that is measured from a base of the matching motor plate to a centerline of a motor shaft of the selected motor, wherein the resulting height of the motor-plate assembly corresponds to a particular height of the direct drive fan assembly; aligning a centerline of the motor shaft of the motor-plate assembly to the direct drive fan assembly, wherein the particular height of the direct drive fan assembly is measured from a top of the motor supports to a center of the hub; changing the motor to a different motor; changing the motor plate to a different motor plate in response to the changed motor, the different motor plate comprising two flanges; matching the different motor to the different motor plate to create a different motor-plate assembly that has a second resulting height that is measured from a base of the different motor plate to a centerline of a motor shaft of the different motor; receiving, by each notch of each motor support, a respective flange of the two flanges of the different motor plate; and aligning the centerline of the motor shaft of the different motor-plate assembly to the direct drive fan assembly, wherein the second resulting height is equal to a different particular height of the direct drive fan assembly that is measured from the notches to the center of the hub, and wherein the direct drive fan assembly includes a frame with components that remain in a fixed arrangement even when the motor-plate assembly is changed. selecting a motor from among a plurality of motors; matching a motor plate from among a plurality of motor plates to the motor, the matched motor plate is based on the selected motor, creating, from the selected motor and the matching motor plate, a motor-plate assembly that has a resulting height that is measured from a base of the matching motor plate to a centerline of a motor shaft of the selected motor, wherein the resulting height of the motor-plate assembly corresponds to a particular height of the direct drive fan assembly; aligning a centerline of the motor shaft of the motor-plate assembly to the direct drive fan assembly, wherein the particular height of the direct drive fan assembly is measured from a top of the motor supports to a center of the hub; changing the motor to a different motor; changing the motor plate to a different motor plate in response to the changed motor, the different motor plate comprising two flanges; matching the different motor to the different motor plate to create a different motor-plate assembly that has a second resulting height that is measured from a base of the different motor plate to a centerline of a motor shaft of the different motor; receiving, by each notch of each motor support, a respective flange of the two flanges of the different motor plate; and aligning the centerline of the motor shaft of the different motor-plate assembly to the direct drive fan assembly, wherein the second resulting height is equal to a different particular height of the direct drive fan assembly that is measured from the notches to the center of the hub, and wherein the direct drive fan assembly includes a frame with components that remain in a fixed arrangement even when the motor-plate assembly is changed.