Rear window dilemma

[Cam-Shaft]

I recently purchased a new cab for my truck as the old one is swiss cheese.

The issue I'm having is with the rear window.

The new cab has the classic small back window



Which is fine.... however I would do just about anything to keep the old's cab large, sliding window... would certainly keep it cool in there during the heat of summer.



Has anyone cut the back of the cab and installed the larger sliding rear window? if the frame has to be welded in, I would happily pay a welder to do it.

Thanks!