Now im really confused.
bought both the brass insert, the seal and the plastic one from VW.
Pulled the injector out with a bit of a struggle, and the unscrewed the old brass bit with a 12mm (which was an effort). The old plastic then dropped out in an engine bay direction. It had NO seal on it.
So i put the new seal onto the plastic thingy, its was a rap fit and wont sit flat at all, its just too big. I then pushed this through the hole in the inlet manifold. Then i screwed on the new brass bit until it went tight and my 12mm allen bit slipped (fcuking the brass). it sits far higher than the other ones, and the plastic sits a bit lower? I then tried pushing the injector through and it wont go for sh!t. I looked down and the seal looks like its stopping it. then, the plastic fell right through?

Does the injector hold the plastic in place or something, i really dont get it. Oh, and the brass bit is firmly stuck in place.
what the hactual f**kuk is going on?