1980s dodge truck doors

Thanks everyone for the pics this helps alot so comparing them to mine it looks like I need to add a piece to the left of the door latch mechanism and I should be fine. The bottom being opened up she be fine structurely. I have no clue why they would have cut that part out on both sides? There was no speakers or anything that high up so it makes no sense to me. I was thinking maybe they did it on the drivers side working on the windows or something but both side? Something doesn't add up.

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