One clue is the square lights - they would have been round in '62.
As Steve mentioned...it is not a good idea to add extra weight to the rear of the trailer - too much stress on the frame, especially a single axle.
What in heavens name would they be carrying in there??? Water jugs - in which case that would be a BIG no-no! Real heavy. Everything bounces around back there - it just accentuates the weight. Kinda like riding in the back of a school bus...
Looks like there is a spare tire carrier between the boxes too...
Shari