Oswald's prints were found on the "Rolling Readers" box inside the sniper's nest. Other than the two at the window, there were no other "Rolling Readers" boxes anywhere near the sniper's nest. The smaller "Rolling Readers" boxes were not among the group of larger boxes needing to moved by the employees laying the floor on the west end of the floor.
The "Rolling Readers" box sitting atop the larger box that was sitting on the floor in the sniper's nest had the prints of law enforcement personnel known to have handled the box after the assassination, an FBI clerk and Lee Oswald.
The FBI took prints from the Depository employees. No other Depository employee left prints on that box. In other words, take out the law enforcement personnel (and the FBI clerk) who handled the box after the assassination and all you have are prints left behind by Oswald.
There is no good reason for those two particular "Rolling Readers" boxes to have been moved to that window, other then to serve as a gun rest. All of the other "Rolling Readers" boxes were three aisles over.
An employee other than Oswald could have placed the two "Rolling Readers" boxes by that window but they did not leave their prints on the boxes and they would have had no reason whatsoever to place those two boxes there. Oswald, on the other hand, touched at least one of those two boxes.
This is not proof that Oswald placed the two "Rolling Readers" boxes inside the sniper's nest, but to say the prints are insignificant because Oswald worked there is to be in simple denial.