Hi Steevo,
You will need to cut the label and remove the end cover. Not sure why it is not sent out cut as most users will need to remove the cover to do updates.
If you look at the sides you will see that the top section away from the antennas is a separate part. Cut the label with a sharp knife between the joins on each side, just enough to cut the label only. Once cut the cover needs to be pushed down in the middle and slid away from the antenna.
Don't understand why the fan area is left clear with no fan fitted, yet the cooling vents over the dongles are blanked off

Picture is worth a thousand words. This is not a Rosetta, but a very similar case.