So here is a picture of the gap with daylight shining through it

On closer inspection it seems as though the front half of the panel ( the part with the clocks and displays on it ) may actually be sealed at the back and that the rear half has its own rubber seal around it and seems to be the meeting point for all the incoming cables and wires. I can't actually see that the two halves are screwed together anywhere so maybe they are all like this and just more or less meet up. I suppose if each half is in itself sealed and the wires running in and out do so in sleeves, there is no reason to worry about the gap between the two halves.
So probably all Streets will look like this, I would imagine (?)
If somebody could take a look at theirs and confirm or negate this I would be grateful......