Leak off pipes: what goes where?

I will be replacing the three worn leak off pipes on my 300 tdi 90. I notice the small copper pipe nearest the bulkhead has nothing connected to it at present but the one nearest the radiator has a plastic pipe on it. I also notice three plastic pipes near the bulkhead "doing nothing"' which may or may not be something to do with the setup. Is this configuration right? How should I reassemble - as existing or some other reconfiguration. Photos attached should explain what I mean. Please excuse my lack of understanding - this is all new to me. Thanks.

The leak off pipe connector nearest the bulkhead is blanked off as it should be.

The other pipes are gearbox/axle breathers and need to be clear and open ended

Thanks for that.