also it helps to have a palm drive ratchet with 1/4 drive deep 7/32 socket ; and make sure you are getting a better quality blend door actuator ; those cheap knock offs from china do not have any stops on the motor at each end of lets say cold and hot so if you motor signal screws up it will keep driving that door flap till it warps or the plastic drive snaps on it ; just beware ; then you will be into some major repairs ;on the back of your actuator the part side that sits against the housing make sure on that drive it has a stop on each end of its travel ;yes the cheap ones do work but if they fail you will wish you had bought that more expensive part
