Stock car doors

Gang,
I finally got my shipment of Accucraft 1/20 stock cars and, as beautiful as they are, door operation is a mystery. The doors are sealed by "wire" in 4 places thru eye bolts attached to the car sides --- which protrude thru angle brackets attached to the doors. Even when the wires are removed, the doors will not slide open (like a box car door) as they are still locked in position by the eye bolts.
The operative question is, how the heck did stock car doors work? If the model is correct (sure hope it is), I can only assume the bottom of the door had to be pulled away from the car side a few inches to clear the eye bolts before it could be rolled open. And based on the position of the eye bolts, it could be re-pinned in the open position for loading. It would not appear to be a free-rolling door like a box car door. Correct?
Any help / info greatly appreciated, Gary