IBM Personal Computer AT Manual To Operations page 73

9
If
the paper width is different from the distance
between the tractors, unlock the tractors by
tilting the tractor lock levers forward and sliding
the tractors to the correct width.
Tractor
....._--..--- Lock
Lever
10
Place the holes of the paper over the tractor pins
and close the tractor covers. Adjust the tractors
so the paper is centered and free of any buckles.
Graphics Printer 1-13