I have done a few of these conversions on dc25 , dc24,07,14,17,23 models
You will need to change the motor and brush bar motor , and the circuit board inl the reset switch which on the 24 luckily comes on the circuit.
Everything else will be fine , the cord and switch are more than capable of handeling the 220volt power, most of these cords and switches are saftey tested to 500v.
machines that are sold in the USA are UL tested , they have the most stringent testing for saftey, machines teseted by UL are ofetn much safer than machines tested by other saftey boards