"This slope and the slope for the opposite side have been shown on either side
of the craft depending on whether one views the box art or the instructions;
therefore the "right" and "left" designation may be considered arbitrary."
This is not correct. The difference between the instructions and the box is not
only that the slopes are switched around, the stickers are also upside down when
comparing the box to the instructions. So left/right is not interchangable. It
actually means that there ought to be four counterparts for these stickers. Two
for each sticker - one for each orientation of the stickers.