Like most of XJS owners I’m chasing after the fuel smell issue in my trunk 
While I was changing vapor lines to fuel vapor separator, I decided to check what is inside the separator.
Actually there is nothing special about it.
I managed to put a small endoscope camera through one of the tubes and took a picture of what’s inside:
Nothing special really… Just 3 long tubes. So there is no actual difference how you connect those 3 thinner tubes.
Only the thicker one is important as it is for draining fuel condensate back to fuel tank. But it is different size so you can’t mix it anyway.