Kinda dumb question

I was looking at an 81F250, 87F150 and a 93F150 that were all parked next to each other the other day and I noticed that the doors and beds and front clips are all similar. Did ford make the trucks all the same for almost 15 years?

81-87 were the same 87-93 i think were the same and 94-96 were the same.For the most part thought the body parts wont interchange.