You'd have to cut open the door and fabricate a brace for the wingvent assembly to bolt onto, then trim away portions of the door skins and the top of the doorframe to create a notch for the assembly to fit into. This could be extra tricky if the window regulator in in the way. You'd still need to find 51-later surrounding trim to cover the hacking scars. Then you need to figure out how the thing is going to latch, as the early turn-down handles won't meet up with the later latches correctly.
In other words, you'd be better off either finding later doors or forgetting the vent windows and just modifying the latch.
