Rear windows for Boxer Van conversion

Hi,
Our Peugeot Boxer Van Conversion (Kingham) has fixed windows on the rear doors.
We would like to find some way of retro fitting sliding openings to allow more ventilation for our dogs.

Has any one seen these on other vans. Or alternatively opening sliders on the very rear side window.

A friend of mind got around the problem by replacing his van with a Nuevo after failing to find a modification to improve ventilation.

Peter Brown wrote:A friend of mind got around the problem by replacing his van with a Nuevo after failing to find a modification to improve ventilation.

Thanks,
But having just shelled out for this van we will have to find a fix