Electric rear window

[LSGarage]

Has anyone ever thought of using an assembly from say a sun roof, that pulls the glass down (or in this case into the cab and away from the window opening) then slids it down. I have a small window cab and have thinking of this for several years. This way the window would still be flush with the outside sheet metal when up. I don't know if the sun roof assembly would be heavy duty enough or not. Just a thought. I don't know if I would have the skills enough to pull it off.