I was throwing away a older above stove microwave. Took it apart and removed the fan. I purchased a roof vent and mounted it to the window well cover w/cut out for vent.
Mounted the fan to a 3/4 in plywood piece sized to the window. I remove the window and install the fan when working w/ca, paint,
micro-balloons, or simple sanding. It also works great for poker night.
Rich