GGR have their own particular way of doing this, which obviously works for them.

But most Breather systems i have had or seen, have the drain on the turbo side of the engine there is a plug in the block towards the back of the engine, you take that out and put a tube fitting in and connect to the bottom of the seperator, the two ongine breathers (if you have the rocker cover one fitted) go to the top of the seperator, and the one left on the seperator goes to the catch tank.

Hope this helps

By the way the pipe 8 thing is actually the pipe size -(dash)8

Cheers: Bart