The picture left shows the generic motor kit I bought on Ebay for around £60. The picture below shows how the motor and the flexible drive can be fitted to the door by means of adjustable brackets and self-tapping screws. The kit includes a wide variety of adapters which allow the business end of the flexible drive to fit on the window winder when the handle is removed. The adapters are made of nylon and unfortunately these can be stripped if the window jams or hits the end of the window’s travel at full speed. (This is where my current limiting circuit comes in handy.)