vent window seal question

[HTX86chevy]

Any one know how to determine the year that the doors or vent windows were made. I see on some websites that there are three different Seal style for different year Trucks.

73-80
81-85
85-91

my passenger door window motor burned up and the motor is from a 70's door.
I am assuming that the door was replaced at some point. I am not sure about the driver side yet. I am hoping to find out a way before pulling the vent windows as this is my daily driver.