I replaced the evaporator fan motor with a new motor from appliance parts. Process was simple: unplug fridge, remove panel in back of freezer, unscrew fan housing from back wall, remove fan blade from existing motor, unplug ground, unplug power and controls harness, put in new fan motor and reverse the order and reinstall the new motor.
Two things were tricky, you may need to defrost your fridge if ice has built up before you turn it back on or before you can remove the back panel. Also don’t forget to remove the plastic spacer from the old fan motor and put it on the new one it prevents the fan blades from hitting the sides of the housing.