Disco 1 Windows in the rear

Is it fairly easy to mount windows in the rear on a 3 door D1 that has the van sort of look? On the inside the panels look very easily removable and on the outside the edges of the would-be window are cracking. I haven't tried removing them, however.

Has anyone done this?

I personally haven't done, no.
But if the panels come out, or can be cut out and you can make a template to take to a glass cutter then they will cut you pieces of laminated glass, which is legal on side windows. Then you'd just need to source some seal, either from a Landy supplier if the windys are the same, in which case they might be able to supply the glass too, or someone like Woolies for trim.
Best of luck

Is it the mid glass? If so then your lucky it appears they are still available standard and tinted left & right, plus the weatherstrip and hinges but they cost a few bob but its a genuine replacement.
The rear sides “ boot space” is just standard D1 five door, and also tinted if required.

The D1 parts catalogue will assist u in part numbers.